The Relationship between Differential Parenting and Children‟s Other-orientedness

by

Sharon Pauker

A thesis submitted in conformity with the requirements for the degree of Masters of Art

Applied Psychology & Human Development University of Toronto

© Copyright by Sharon Pauker 2013

ii

The Relationship between Differential Parenting and Children‟s Other-orientedness

Sharon Pauker

Master of Arts

Applied Psychology and Human Development

University of Toronto

2013

Abstract

The current study examined whether there is a curvilinear association between

differential parenting and children‟s Theory of Mind (ToM) and two similar abilities

we defined as “ToM- in-Action”. These were, use of perspective taking language

and cognitive sensitivity (providing tailored verbal or non-verbal guidance) while

completing a challenging task with a younger sibling. A community sample of 372

children (52% were males, average age=5.6), their younger siblings (average

age=3.14) and their mothers were observed in their homes. Acknowledgments (if

any) Findings showed a linear association rather than a curvilinear effect, where

favored older siblings had significantly poorer cognitive sensitivity and

perspective taking when interacting with their younger sibling in a challenging

task. This relationship remained significant when other variables such as age and

SES were controlled. The relationship between differential parenting and ToM

was non-significant. Results demonstrate the specific and complex impact of

differential parenting on children‟s social cognition.

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Acknowledgements

First and foremost I would like to thank to my supervisor, Dr. Michal Perlman, for her

continuous support and guidance throughout this process. You always made yourself

available and provided me with insight and useful feedback. I feel very fortunate to

have a supervisor who is so kind and considerate of her students.

I would also like to thank my committee member, Dr. Jennifer Jenkins, for providing me

with the framework for this thesis. I greatly appreciate the advice and knowledge you

offered me over the past 2 years.

Furthermore, I would like to thank the families and staff members involved in the Kids,

Families and Places Study. Your involvement made this research possible.

In addition, I would like to thank my classmates for always encouraging and supporting

me. The relationships that we have formed during this time are clearly life long and very

meaningful.

Last but not least, I thank my parents and my husband – you are my inspiration. Your

endless love and support has given me the courage to pursue my dreams.

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Table of Contents

Acknowledgements ......................................................................................................... iii

List of Tables................................................................................................................... vi

1 Introduction .................................................................................................................. 1

1.1. Differential Parenting and its impact on children and their sibling relationship quality .......................................................................................................................... 1

1.2. Differential Parenting and Social Cognition .......................................................... 4

1.3 Theory of Mind ....................................................................................................... 5

1.4 Perspective Taking ................................................................................................ 7

1.5 Cognitive Sensitivity ............................................................................................... 8

1.6 Covariates ............................................................................................................. 8

1.7 The Current Study ................................................................................................. 9

2 Methods ....................................................................................................................... 9

2.1 Participants ............................................................................................................ 9

2.2 The Current Study ............................................................................................... 10

2.3 Measures ............................................................................................................. 10

2.3.1 Independent Control Variables ................................................................... 15

2.4 Data Analysis ....................................................................................................... 15

2.5 Missing Data ........................................................................................................ 16

3 Results ....................................................................................................................... 16

3.1 Preliminary Analysis ............................................................................................ 16

3.2 Main Analyses ..................................................................................................... 18

3.2.1 Model 1: Theory of Mind ........................................................................... 18

3.2.2 Model 2: Perspective Taking .................................................................... 18

3.2.3 Model 3: Cognitive Sensitivity ................................................................... 21

4 Discussion ................................................................................................................. 21

v

5 Limitations ................................................................................................................. 26

6 References ................................................................................................................ 28

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List of Tables

Table Page

Table 1 Bivariate Pearson/point biserial correlations, Means and 17

Standard Deviations…………………………………………

Table 2 Summary of hierarchical regression analysis examining 19

the role of differential sensitivity in predicting Theory-of-

Mind…………………………………………………………..

Table 3 Summary of hierarchical logistic regression analysis 21

examining the role of differential sensitivity in predicting

sibling perspective taking………………………………….

Table 4 Summary of hierarchical regression analysis examining 23

the role of differential sensitivity in predicting sibling

cognitive sensitivity……………………………………….

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1 Introduction

1.1. Differential Parenting and its impact on children and their sibling relationship quality

Differential Parenting has been researched extensively since the seminal work of

Plomin and Daniels in 1987. These authors argued that children in the same family are

different than one another due to experiences in their nonshared environment. One

aspect of the nonshared environment refers to the different ways each parent treats

each of his or her children (i.e., differential parenting). Differential parenting refers to the

degree to which parents display unequal treatment toward their children in terms of the

amounts of negativity, control, sensitivity and warmth they direct to each child. Moderate

amounts of differentiation may reflect sensitive parenting, as the parent adjusts his or

her treatment of each child based on the child‟s distinctive needs (Brody, Stoneman, &

McCoy, 1992; Meunier, Bisceglia, & Jenkins, 2012). However, greater amounts of

differential parenting and harsh parenting predict children‟s propensity for behavioral

problems (Tamrouti-Makkink, Dubas, Gerris, & van Aken, 2004). Research suggests

that differential treatment may be driven both by differences between siblings and stress

on parents. Child effects on differential parenting may include gender, age, and

temperament (Jenkins, Rabash, &, O‟Connnor, 2003). Parental effects may include

social disadvantage (Jenkins, Rabash, & O‟connor, 2003) and parental personality traits

(Browne, Meunier, O‟connor, & Jenkins., 2012). Overall, differential parenting was found

to increase children‟s risk of later behavior problems (Caspi et al., 2004; Burt, McGue,

Iacono, & Krueger, 2006).

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Studies have consistently shown that children who receive less favorable

treatment than their siblings, present with more externalizing and internalizing behavior,

as well as with lower self-esteem and self-worth (Dunn, Stocker, & Plomin, 1990;

McHale, Updegraff, Jackson-Newson, Tucker, & Crouter, 2000; Singer & Weinstein,

2000; Scholte et al., 2007). Social Comparison Theory (Festinger, 1954) has been

used in understanding these findings. This theory asserts that individuals have an

intrinsic drive to evaluate their own opinions and abilities through self-comparison with

others, particularly to those who are perceived as similar. Considering that siblings

share their environment and family background, they are likely to engage in self-

comparison (Whiteman, McHale, & Soli, 2011). Disfavored siblings who engage in

social comparisons with their favored siblings are likely to experience negative self-

evaluation, which may lead to suboptimal functioning and compromised sibling

relationships (Shanahan et al., 2008). Findings of positive outcomes for favored siblings

are limited. In a large twin and step families study, Reiss, Hetherington, Plomin and

Howe (1995) found that in families where one child received greater amounts of

negativity, the sibling presented with less antisocial behavior. Likewise, in families

where greater amounts of warmth were directed to one child, the sibling presented with

more depressive symptoms. These authors named this phenomenon the “sibling

barricade”. In contrast, other studies have suggested that differential parenting may

result in negative outcomes for all siblings in the family (Boyle et al., 2004) and that at

least for some outcomes excessive amounts of differentiation are likely to have

deleterious effects on a child regardless of whether he or she is being favored or

disfavored (Suitor et al., 2008; Meunier, Bisceglia, & Jenkins, 2012; Meunier et al.,

2013). For example, Rauer and Volling (2007) found that although siblings who received

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more parental affection reported decreased sibling jealousy and higher self-esteem

(compared to disfavored siblings), they also experienced high rates of romantic

relationship distress. Furthermore, favored siblings were more likely than disfavored

siblings to classify their attachment style as insecure (i.e., dismissive or fearful). These

findings are consistent with Zervas and Sherman‟s (1994) conclusion that individuals

who are treated equally within a family present better outcomes than those who are

being either favored or disfavored.

Deutsch (1985) developed the idea of distributive justice and argued that individuals

experience a negative emotional reaction when an inequality that is perceived as unjust

occurs. Thus, both favored and disfavored children in a family should perceive

differential parenting as violating the principles of distributive justice. Kowal and

colleagues (2002) used distributive justice theory to explain the findings that differential

parenting is harmful to all children within the family. However, it should be noted that

differential parenting does not appear to impact all children in a family equally. That is,

for the outcomes that have been studied to date, disfavored children tend to be

impacted more negatively by differentiation than their favored siblings (Burt, McGue,

Iacono, & Krueger, 2006; Meunier et al., 2013).

Finally, Social Learning Theory (Bandura, 1977), has been used in explaining the

erosion of the sibling relationship as a result of differential parenting, rather than each

child‟s outcomes. According to this theory, an individual acquires new behaviors and

cognitive attitudes through observation and reinforcement of others‟ behavior. Parents

and older siblings are most likely to be imitated if they are perceived as powerful and

competent (Bandura, 1977). Consistent with this theory, perhaps part of the erosion of

the sibling relationship quality that is associated with differential parenting reflects

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children imitating maladaptive interactions that their parents model. A child, who

consistently witnesses his or her parent directing high levels of control and aggression

toward his or her sibling, might replicate this harsh behavior pattern when interacting

with that sibling. Supporting this notion, Perlman and Ross (1997) suggested that

children model parental control strategies during sibling conflicts.

1.2. Differential Parenting and Social Cognition

Advanced social cognitive skills such as understanding others‟ emotions and

perspective taking (Fenning, Baker, & Juvonen, 2011) predict children‟s later adaptive

outcomes (Denham et al., 2003), whereas deficits in social cognition have been found

to be correlated with externalizing behavior (Denham et al., 2002) and peer rejection

(Dekovic´ & Gerris, 1994). One hypothesis regarding the development of social

cognition asserts that it is constructed through accumulated experiences, specifically

through parent-child interactions. Dyadic communication is perceived as essential to the

development of social cognition (Dodge, 2006). Furthermore, Vygotsky (1931;1997)

claimed that social understanding is rooted in interpersonal exchanges which are then

internalized by the individual (Fernyhough, 2008).

While there is a large body of research examining the influence of differential

parenting on children‟s behavioral and adjustment outcomes, little if any work has been

done on differential parenting and social cognition. We focus on a specific aspect of

social cognition: other-orientedness - a child‟s ability to understand his or her sibling‟s

perspective, thoughts, beliefs, and to cooperate with him or her. In order to measure

children‟s other-orientedness, we administered ToM tasks in addition to measures of

perspective taking and cognitive sensitivity. These are described below.

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1.3 Theory of Mind

ToM is a complex skill of understanding and predicting another‟s psychological

state (e.g., feelings, beliefs, and desires; Premack and Woodruff, 1978). Advanced ToM

capacity in children has been linked to social competence (Astington & Jenkins, 1995),

whereas deficits in ToM are associated with behavioral abnormalities, such as autism

and schizophrenia (Baron-Cohen, Leslie, & Frith, 1985). Thus, ToM acquisition is

central in the development of social competence. Numerous studies have examined

ToM in order to understand this mechanism. Particular attention has been given to

variables that predict ToM. Early research suggested ToM to be a maturational process

that is not influenced by environmental factors (Leslie, 1994). However, children are

highly variable in ToM acquisition, which may in part be explained by early social

experiences (see Carpendale & Lewis, 2004; 2006); cross-cultural influences (Vinden,

1999; Wellman et al., 2001) and genetic effects (Hughes & Cutting, 1999). However,

according to a more recent twin-study, with a large sample size, conducted by Hughes,

Jaffee, Happe´, Taylor, Caspi, and Moffitt (2005), no genetic effects were found for

ToM. Further, research findings indicated that 44% of the variance in ToM among twins

was explained by non-shared experiences, and differential parenting in particular. Thus,

differential parenting may accelerate ToM understanding. Since Leslie‟s work in 1994, a

line of studies has looked into the impact of familial experiences on ToM acquisition.

Perner and colleagues (1994) were the first to show that children who had siblings

scored higher on measures of ToM than children without siblings in a family. Astington

and Jenkins (1996) replicated these results with the exception that children with

stronger language skills were not affected by having a sibling. The number of siblings in

a family has also been linked to better ToM (false-belief) ability (Lewis et al., 1996).

6

However, perhaps the quality of the relationship, rather than the mere presence or

absence of a sibling, is the factor that plays a role in accelerating ToM ability (Hughes,

Deater-Deckard, & Cutting, 1999; Hughes & Ensor, 2005). Another line of research has

shown that early experiences such as a secure attachment style (Fonagy et al. 1991;

Meins 1997; Meins, Russell, & Clarck-Carter, 1998; Symons & Clark 2000), maternal

discourse, with an emphasis on mental state talk (see Symons, 2004 for a review), and

maternal mind mindedness (i.e., the tendency of a mother to treat her infant as an

individual with a mind and ability of intentional behavior; Meins et al., 2002) were

associated with ToM.

While understanding another‟s mental state involves a larger range of social

cognitive skills, the majority of the aforementioned studies used only false-belief tasks

(i.e., the ability to judge information provided to an individual when interpreting and

predicting the individual‟s action; even if the information is not compatible with one‟s

own) to measure children‟s ToM. False-belief tasks do not include any social interaction,

but rather are solely directed toward evaluating a child‟s cognitive ability. Consistent

with the growing recognition that ToM research should encompass a fuller spectrum of

mental states (Hughes & Leekam, 2004), we added two measures of social cognition:

(1) perspective taking (i.e., the extent to which a child recognizes that his or her

interaction partner has their own point of view. This recognition is reflected in the kind of

language and reasoning a child directs towards their partner), and (2) cognitive

sensitivity (i.e., the ability to provide tailored and sensitive guidance in teaching a novel

task). We defined these two skills as “ToM-in-Action” because they capture children‟s

abilities to understand others within the context of social interaction rather than within a

purely cognitive task. Perspective taking and cognitive sensitivity were evaluated

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through observations of a child interacting with a younger sibling, and provided us with

rich evidence on the subjects‟ other-orientedness skills.

1.4 Perspective Taking

Perspective taking was defined by Hoffman (1984) as a cognitive process that

allows one to understand another‟s mental state and includes the explicit ability of

taking another‟s perspective. This skill promotes prosocial behavior, compassion, and

empathy (Hoffman, 1984). According to Premack and Woodruff (1978) ToM is a form of

perspective taking.

Perspective taking has been operationalized differently across various studies.

For instance, emotional/affective perspective taking is described as the ability to

explicitly interpret others‟ emotions or feelings (Hughes & Dunn, 1998; Harwood &

Farrar, 2006). Visual perspective taking refers to the ability to appreciate how the world

looks from another‟s perspective (Bigelow & Dugas, 2009). In the current study,

perspective taking included a combination of two skills: reasoning and internal state talk

because both reflected children‟s understanding that they must explain, justify and

elaborate their responses to their interaction partner. Such perspective taking can occur

during a play interaction, for example, when a child‟s request for blocks from their

siblings is accompanied by reasoning: “I need this block because without it my castle

will collapse”. Internal state talk was also utilized in this sentence as the child expressed

a desire (i.e., I need) and a statement of ownership (i.e., my castle). In the literature,

affective perspective taking was found to be significantly related to but not overlapping

with ToM (Denham, 1986; Harwood & Farrar, 2006), suggesting that the two skills are

different representations of cognitive empathy (Farrant et al., 2011).

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1.5 Cognitive Sensitivity

Cognitive sensitivity captures an individual‟s ability to correctly assess the

knowledge and state of mind of their partner while cooperating to reach a shared goal

(Prime et al., in press). It is comprised of three processes: building mutuality, mind-

reading, and communicative clarity.

In the current study, we examined pre-school aged children‟s cognitive sensitivity

skills while they interacted with their younger siblings. Cognitive sensitivity was

operationalized as the ability of a child to provide tailored guidance in teaching a

challenging and novel task to a younger sibling. This measure required the child to be

sensitive, cooperative and to perceive his or her younger sibling‟s mental state, point of

view, and knowledge capacity in order to provide the sibling with the appropriate and

comprehensible directions. As ToM understanding requires an individual‟s

representation of another‟s mental states, ToM should be linked to cognitive sensitivity

ability. Findings of associations between ToM and children‟s teaching skills (Strauss et

al., 2002; Davis-Unger & Carlson, 2008; Prime et al., in press) support this notion.

1.6 Covariates

Past research has suggested that variables such as: gender differences in false-

belief (Charman, Ruffman, & Clements, 2002; Happe´, 1995), age (Wellman, Cross, &

Watson, 2001; Onishi & Baillargeon, 2005), language (e.g., Astington & Jenkins, 1999;

Hughes & Dunn, 1998; Jenkins & Astington, 1996), mother‟s educational attainment

(Cutting & Dunn, 1999; Meins & Fernyhough, 1999), and social economic status (Cole &

Mitchell, 1998; 2000; Cutting & Dunn, 1999; Holmes, Black & Miller, 1996) are all

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correlated with ToM ability. Therefore, in the current study these variables were

controlled in the data analysis.

1.7 The Current Study

The present study expands on the differential parenting literature by examining whether

differential parenting is associated with pre-school children‟s social cognitive ability.

Specifically, is differential parenting related to children‟s other-orientedness skills (ToM,

perspective taking, and cognitive sensitivity). Thus, our goal in the current study was to

explore whether differential parenting cross-sectionally predicted other-orientedness

skills above and beyond covariates (described below). Specifically, in contrast with

social comparison theory (Festinger, 1954), and consistent with growing evidence that

suggest that differential parenting negatively affects all children in a family (Boyle et el.,

2004; Meunier, Bisceglia, & Jenkins, 2011; Meunier et al., 2013), as well as with

distributive justice theory (Deutch, 1985), a curvilinear association was hypothesized

between differential sensitivity and ToM, such that, in families with higher rates of

differentiation, children were expected to present lower other-orientedness abilities. As

both perspective taking and cognitive sensitivity measures were captured through

sibling interactions, we expected them to be influenced by various family dynamics

(e.g., differential parenting).

2 Methods

2.1 Participants

The current study is embedded within a larger longitudinal birth-cohort study.

The goals of the larger study were to examine genetic and environmental influences on

children‟s socio-emotional development using a sibling design. Participants were

10

recruited through a program called Healthy Babies Healthy Children, run by Toronto and

Hamilton Public Health, which contacts the parents of all newborn babies within several

days of the newborn‟s birth. To be eligible families had to have a newborn child (called

Sibling 1) with birth-weight being over 1500 grams, a sibling who was less than 4 years

old (called Sibling 2), and an English speaking mother. Five-hundred and one families

make-up the sample data collection. Using 2006 Canada Census Data, the sample was

similar to the general population in terms of number of persons in the household and

personal income, but had a lower proportion of non-intact families, fewer immigrants

and more educated mothers (Meunier, Bisceglia, & Jenkins, 2012).

2.2 The Current Study

Data from the third wave of data collection when younger children were 3 and

older siblings were on average 5.5 years-old was used in the present study. Data was

gathered through questionnaires for mothers and videotaped siblings‟ interactions and

an interaction of mother with each of her children. The ages of the older siblings

represent a sensitive developmental period in theory of mind development, whereas the

younger siblings are at an age where false-belief understanding is unlikely to be evident

(Astington, Harris, & Olson, 1988; Gopnik & Wellman, 1994; Perner, 1991; Wellman,

1990; for a review, see Wellman, Cross, & Watson, 2001). As such, the older siblings

were the focus of our exploration into individual differences. (N=372, males=192, M

age=5.57, SD=0.77, range 4-7.67).

2.3 Measures

Theory of Mind. The Wellman & Liu (2004) scale was used to capture ToM. The

scale includes different tasks presented in a sequential order which target children‟s

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development of theory of Mind understanding. Higher scores reflect a more complex

Theory of Mind understanding. In addition to the Wellman and Liu scale , we included a

second order belief question (Astington, Pelletier, & Homer, 2002) to promote the

variability in children‟s performance. The testing session was ended once children failed

two consecutive tasks on the scale. All theory-of-mind tasks were presented through

stories which were enacted for children with the use of puppets and props (or pictures,

i.e. 2nd order false belief). For each of the tasks, the child is given a score of 0 (fail) or 1

(pass). A mean was taken across tasks and the internal consistency of the scale was α

= .81.

Cognitive Sensitivity. Sibling pairs were filmed engaging in a cooperative

building task (Aguilar et al., 2001). Dyads were instructed to sit on a yoga mat and use

Duplo building blocks to build a picture of a design in 5 minutes. They were each only

allowed to touch two of the four colours of Duplo blocks used in the model to ensure

collaboration for completion. Interviewers were present in the room with the dyads

during the task but did not provide instructions beyond protocol. If children finished the

design before the end of five minutes, they were given a second model to build. All

children were stopped after five minutes, regardless of completion. The majority of

dyads were engaged with the task for 80% or more of the five minutes.

Videotapes of sibling interactions were coded using a measure of cognitive

sensitivity (Prime et al., 2013).The measure addresses three linked capacities of mind-

reading, mutuality, and communicative clarity. Coders watched the 5-minute film clip in

its entirety and then rated the older sibling on a 5-point likert scale, ranging from „Not at

all true‟ (1) to „Very true‟ (5) on each of the eleven cognitive sensitivity statements.

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Items started with „This person is…‟ and examples include: sensitive to what his/her

partner knows and/or understands; good at rephrasing what his/her partner does not

understand; gives positive feedback to reinforce his/her partner; clear in his/her

requests for help. This approach provides comparable reliability and validity to a more

time intensive observational coding method while requiring fewer resources (Prime et

al., 2013). The mean was taken across items and internal consistency of the composite

was high, α = .89. Coders included a mix of undergraduate and graduate students who

were trained by an expert coder. Inter-rater reliability was tested by double-coding ten

percent of the interactions and reliability checks were carried out throughout the coding

period to minimize drift. Disagreements were resolved by taking a mean of the coders‟

judgments. Inter-rater reliability on the composite score was acceptable, α = .72. All

coders were blind to the hypotheses of the study.

Perspective Taking. Sibling dyads were video recorded completing the

aforementioned Duplo building blocks task. Family interaction was coded using interval

coding similar to work done by Volling, McElwain, and Miller (2002), Howes and

Matheson (1992), and Perlman & Fletcher (2012), who used it to capture interactions in

other contexts. Coders code the interaction based on fifteen 20 seconds intervals. In

each one of the 15 snapshots observers coded internal state talk (i.e., desire, emotion,

belief, and statement of ownership) and reasoning (e.g., justification, explanations)

expressed by each sibling. If a reasoning or internal state talk were observed, the child

received a score of 1 for that code for that snapshot. A final perspective taking score

was computed by summing up all the snapshots in which reasoning and internal state

talk were observed for each child. As the distribution was zero inflated, the final

perspective taking score was dichotomized. Subjects who had a final score greater than

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zero were assigned the value of 1. Subjects who had a final score of zero, kept that

score. As the distributions of each of the variables that make-up the perspective taking

construct (i.e., reasoning and internal state talk: desire, belief, emotion, statement of

ownership) were zero inflated as well, they were all dichotomized, using a similar

procedure to the one described above. In order to measure the construct‟s internal

consistency value, a polychoric factor analysis was conducted in Stata (SE 12.0

version), due to the binary nature of all variables included in the perspective taking

construct. Initial eigenvalues showed that the first factor explained 82% of the variance.

All five variables that make-up the perspective-taking construct showed factor loadings

ranging between 0.37-0.7. Inter-rater reliability Kappa values were 0.86 for each of the

siblings.

Mother-child Interaction. Mother was video recorded interacting with each child

across a 5-minute building task and a 5-minute free play period. The building task was

similar to the siblings‟ Duplo building blocks task described above. During free play,

mother and child were instructed to play for five minutes with no toys (Aguilar et al.,

2001). Mother and child were instructed to sit in front of the camera on a “magic carpet”

(yoga mat) while the camera was set to capture their full body. The two interactions

were coded using a scale integrating the Coding of Attachment-Related Parenting

(CARP; Matias, 2006) measure, and the Parchisy (PAR; Deater-Deckard et al., 1997)

assessing three domains of responsivity (i.e., sensitivity, mutuality, and positive control).

Mother‟s sensitivity code (CARP) evaluated the extent to which she promoted her

child‟s autonomy, showed warmth, provided the child with appropriate verbal and non-

verbal feedback, and was able to take her child‟s perspective. The mutuality code

(CARP) targeted the mother-child dyad and is consistent with the concept of “goal-

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corrected partnership” (Bowlby, 1982). It assessed the reciprocity in the dyad dialogue,

affect sharing, joint engagement in task, and open body posture. The positive control

code (PARCHISY) was indexed by the mother‟s ability to direct her child through the

task using praise, open-ended questions and clarifications. Each of these codes was

rated on a 7-point-likert scale, with a higher score indicating higher levels of the targeted

behavior. Reliability was assessed through double-coding of 10-25% of total interactions

(composite α=.903). A final maternal sensitivity score was computed by calculating the

mean for all three measures (composite internal consistency α=.79).

Differential Sensitivity. A differential sensitivity score was computed using a

multilevel modeling approach in order to partial out the effect of child age. Differential

parenting is highly associated with age of children, specifically with regards to

differential positivity (Jenkins, Rasbash, & O‟Connor, 2003). According to Jenkins and

colleagues, age was found to be a very strong predictor of differential parenting, where

older children received more positive treatment than younger children, and middle

children were treated less positively than younger children. In order to partial out the

effect of age on differential sensitivity, a multilevel regression was performed using a 2-

level model in Stata (SE 12.0 version) with maternal sensitivity (raw score) as the

dependent variable and with children‟s age as the predictor. Regression residuals were

then saved and represented the amount of maternal sensitivity directed to each child

after accounting for the effects of age. Next, younger siblings residual values were

subtracted from those of the older siblings to produce a result of older siblings‟

differential sensitivity score, after accounting for the fixed and random effects of age.

Higher scores on this measure represent being favored.

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Curvilinear Effect- Differential Sensitivity Quadratic Term. A quadratic term

for differential parenting was computed. In order to reduce multicollineraity between the

linear and the quadratic differential sensitivity terms (Aiken & West, 1991), the quadratic

term was computed using centered differential sensitivity values.

2.3.1 Independent Control Variables

Demographics. Child gender (with boys as the reference category), age (was

measured in years), socioeconomic status and mother‟s education level were included

as covariates. Socioeconomic status variable was comprised of income and assets. To

assess assets the following questions were used: “how many rooms do you have in

your house”; “Do you own or co-own this home/apartment/unit, even if still making

payments”; “Do you own or co-own a car, even if still making payments”. Annual income

was also reported (M= $65,000 - $74,999). Assets and income items were standardized

and a mean was computed, with higher scores indicating higher SES (α = .79). Mothers‟

education level was measured through their reports on the number of years of

education they completed, including secondary and post-secondary education. The

mean education level was 15.53 years (SD=2.47, range 10-22).

2.4 Data Analysis

Two hierarchical linear regressions and one hierarchical logistic regression were

conducted in order to examine the relationship between differential parenting and ToM,

sibling cognitive sensitivity and perspective taking. At step 1 the following variables

were entered in the model: age, gender, socio-economic status, language, and maternal

sensitivity toward target child. At step 2 we added differential sensitivity as a predictor.

Finally, at step 3, the quadratic term for differential sensitivity was entered in the model.

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2.5 Missing Data

Missing data on mothers‟ reports, observational and child testing measures

ranged from 0 to 17 %. These missing cases if dropped from the analysis can result in

reduction of the statistical power and bias the estimates of parameters (Allison, 2003).

Multiple imputation analysis was conducted to avoid loss of participants (Rubin, 2003).

Multiple imputation analysis was performed using SPSS (version 21) and generated 5

complete datasets that included the covariates, predictors and outcome variables. Each

regression analysis was run across all 5 datasets and produced pooled estimates for all

coefficients.

3 Results

3.1 Preliminary Analysis

Variable means, standard deviations, bivariate pearson and point biserial

coefficients are presented in Table 1. Pearson and point biserial coefficient values

present weak to moderate correlations (-0.17< to r< 0.55). Preliminary bivariate

associations for cognitive sensitivity showed that it was significantly positively

associated with children‟s age, language skills socioeconomic status, perspective

taking, ToM understanding, and with maternal sensitivity. Additionally, cognitive

sensitivity was found to be significantly negatively associated with children‟s gender and

with differential sensitivity. That is, disfavored older girls and children with advanced

language, perspective taking skills and Theory of Mind understanding, and children who

came from higher socioeconomic status households, were more likely to present with

higher cognitive sensitivity. With regards to perspective taking, preliminary bivariate

associations showed that this skill was significantly positively associated with children‟s

17

age, language skills, cognitive sensitivity and ToM. Moreover, perspective taking was

significantly negatively associated with children‟s gender and with differential sensitivity.

Specifically, disfavored older girls, children with higher language skills and children with

advanced cognitive sensitivity and Theory of Mind abilities, were more likely to use

perspective taking language when completing a challenging task with their younger

sibling.

Measures 1 2 3 4 5 6 7 8 9 10 11 M SD

1.Child Age - 5.57 0.77

2.Child Gender 0.08 - - -

3.Child Language

-0.02 -0.02

- 107.51 13.44

4. Mother education

0.01 -0.03

0.29** - 15.56 2.48

5. SES (assets, income)

-0.07 0.15

0.4** 0.88

** - 0.03 0.71

6. Mother Sensitivity

-0.10

* 0.06 0.38

** 0.33

** 0.41

** - 4.25 0.85

7. Differential Sensitivity

-0.13

*

0.12* 0.06 0.02 0.06 0.55

** - 0.07 0.43

8. Cognitive Sensitivity

0.28** -0.1

* 0.15

** 0.18

** 0.21

** 0.12

* -0.17

** - 2.58 0.71

9. Sibling Perspective

Taking

0.16** -

0.04 0.17

** 0.06 0.09 0.08 -0.11

* 0.40

** - 0.86 .35

10. Theory of Mind

11.Differential Sensitivity- Quadratic Term

0.47**

-0.06

0.01

0.11*

0.32**

0.01

0.14*

0.05

0.20**

0.04

0.15**

-0.00

-0.04

-0.06

0.32**

-0.06

0.23**

-0.03

-

-0.02

-

4.54

0.76

2.09

1.04

Note: *p < .05, **p < .01

Table 1. Bivariate Pearson/point biserial correlations, Means and Standard Deviations

18

3.2 Main Analyses

Three separate hierarchical regression models were conducted to assess the

relationship between the predictor, differential sensitivity and each of the dependent

variables, sibling perspective taking and sibling cognitive sensitivity (i.e., ToM-in-Action

variables), and Theory-of-Mind. Hierarchical regression was selected because it allowed

us to evaluate the unique contribution of the predictor to the model, above and beyond

covariates.

3.2.1 Model 1: Theory of Mind

Results for hierarchical regression examining the relationship between differential

sensitivity and ToM can be found in Table 2. At the first step, the covariates accounted

for a significant amount of the variance in the model, R2=.28, F(6,365)=24.15, p<.001.

Target child‟s age and language skills were found to be significant predictors of ToM

understanding. That is, being older and having stronger language skills were associated

with higher scores on ToM understanding scale. At step 2, differential sensitivity was

included in the model, but it did not explain any more variance in the model, R2

change=.003, F(7, 364)=1.6, p=.3. Thus, differential sensitivity was not significantly

associated with ToM ability. Similarly, at step 3, the differential sensitivity quadratic term

did not explain any additional variance in the model, R2 change<.001, F(8, 363)=.08,

p=.8. These results suggest that differential sensitivity has no curvilinear effect on ToM

understanding scores.

3.2.2 Model 2: Perspective Taking

Results for hierarchical logistic regression examining the relationship between

differential sensitivity and sibling perspective taking can be found in Table 3. In step 1,

19

Theory-of-Mind B SEB β

Covariates

Child gender -0.031 0.024 -0.06

Child age 0.150 0.016 0.444***

Mother education -0.006 0.075 -0.056

Socioeconomic status 0.035 0.079 0.091

Child language skills 0.005 0.051 0.232***

Maternal sensitivity 0.033 0.068 0.106

Predictor

Differential sensitivity -0.019 0.063 -0.063

Curvilinear effect

Differential sensitivity-Quadratic term 0.001 0.047 0.003

Note: ***p < .001, adjusted R2=0.27

Table 2. Summary of hierarchical regression analysis examining the role of differential sensitivity in predicting Theory-of-Mind.

the covariates accounted for a small but statistically significant amount of the sibling

perspective taking variability (Nagelkerke R2 =.06, χ2(6,365)=17.7, p=.01. Child age and

language skills were found to be significant predictors of sibling perspective taking,

where each additional point increase on language skills test increases the odds of using

perspective taking language by 2.4%. In addition, with each year increase in a child‟s

age, he or she were about 47% more likely to use perspective taking language. At step

2, inclusion of differential sensitivity, explained additional 2.2% of variance in the model,

Nagelkerke R2 =.082, χ2(7, 364)=6.44, p=0.02. Differential sensitivity was found to be a

20

significant predictor of sibling perspective taking, such that, each additional unit

increase in mother‟s differential sensitivity toward a target child (being favoured),

decreases the likelihood of that child using perspective taking language towards his/her

younger sibling by about 40%. Lastly, at step 3, differential sensitivity quadratic term did

not significantly explain any additional variance in the model (only explained additional

.001% of the variance) Nagelkerke R2=0.083, χ2(8,363)=..24, p=.65. These results

suggest that there is no curvilinear effect of differential sensitivity on children‟s

perspective taking ability.

Perspective Taking B SE Exp(B)

Covariates

Child gender -0.031 0.253 0.969

Child age 0.370 0.147 1.448*

Mother education 0.016 0.101 1.016

Socioeconomic status -0.145 0.359 0.865

Child language skills 0.021 0.010 1.021*

Maternal sensitivity 0.298 0.193 1.347

Predictor

Differential sensitivity -0.382 0.184 0.683*

Curvilinear effect

Differential sensitivity-Quadratic term -0.042 0.115 0.959

Note: *p < .05, **p < .01, ***p < .001, Nagelkerke R2=0.08

Table 3. Summary of hierarchical logistic regression analysis examining the role of differential sensitivity in predicting sibling perspective taking.

21

3.2.3 Model 3: Cognitive Sensitivity

Finally, a hierarchical regression was conducted to examine the relationship

between differential sensitivity and sibling cognitive sensitivity (Table 4). At step 1, the

covariates accounted for a significant amount of the variance in sibling cognitive

sensitivity, R2= .12, F(6, 365)=9.23, p<0.001. Child gender and age were found to be

significant predictors of sibling cognitive sensitivity skills. That is, being older was

associated with better cognitive sensitivity directed toward younger sibling. Additionally,

female participants were more likely to use cognitive sensitivity when interacting with

their younger sibling. At step 2, entering differential sensitivity explained additional 3.8%

variance in the model, R2 change=.038, F(7, 364)=17.02, p<.001. Results showed that

directing more sensitivity toward an older child (i.e., being favoured) was a significant

predictor of his or her cognitive sensitivity skills, such that, the more he or she was

being favored, the poorer their cognitive sensitivity towards their younger siblings. In

addition, the inclusion of differential sensitivity in the model contributed to the change in

maternal sensitivity covariate to become statistically significant as well. That is, children

who receive more maternal sensitivity are more likely to present better cognitive

sensitivity skills. Lastly, at step 3, differential sensitivity quadratic term was included in

the model. The quadratic term did not explain any additional significant variance in the

model, R2 change=0.002, F(8, 363)=1.07, p=.32. Thus, these results indicate the

absence of a curvilinear effect in differential sensitivity on cognitive sensitivity ability.

4 Discussion

The goal of the present study was to explore the relationship between children‟s

other-orientedness and differential parenting. To date, no other research in the

22

differential parenting literature has addressed this question. The current study

contributes to this field, firstly by attempting to fill this gap using a representative sample

of Canadian children ages 4-7. Secondly, the present study introduces a novel

measure, ToM-in-Action. ToM-in-Action includes two different observational measures

that were coded using two different coding techniques (i.e., global coding of cognitive

sensitivity and interval coding of perspective taking). Thus, one of the strengths of this

study is that it employed a multiple-measure approach in evaluating other-orientedness

ability on a large sample of families. Further, the present study measured differential

parenting using observations of mother-child interactions.

Cognitive Sensitivity B SEB β

Covariates

Child gender -0.199 0.051 -0.141**

Child age 0.246 0.051 0.269***

Mother education -0.007 0.083 -0.023

Socioeconomic status 0.144 0.095 0.141

Child language skills 0.002 0.057 0.04

Maternal sensitivity 0.151 0.073 0.182*

Predictor

Differential sensitivity -0.193 0.064 -0.242***

Curvilinear effect

Differential sensitivity-Quadratic term -0.033 0.05 -0.049

Note: **p < .01, ***p < .001, adjusted R2=0.15

Table 4. Summary of hierarchical regression analysis examining the role of differential sensitivity in predicting sibling cognitive sensitivity.

23

The novel ToM-in-Action variables, cognitive sensitivity and perspective taking

provided us with richer understanding of ToM as it is applied by young children during a

challenging sibling interaction. Even though the two skills were coded in two different

coding techniques by different sets of coders, the pattern of results using both bivariate

correlations and regression coefficients were similar. This indicates that the two

measures are capturing similar abilities in different ways. Our initial aim of using ToM-in-

Action variables was to examine ToM understanding in the context of an interaction

where the setting is more naturalistic for the child to use this skill compared with a false-

belief task. Our findings support this and would allow future studies to operationalize

ToM in a wider array of contexts.

Consistent with Distributive Justice Theory (Deutch, 1985), we expected that

higher rates of differential parenting would be detrimental for both children in terms of

their ToM and ToM-in-Action skills. Our results confirmed this for favored children.

Interestingly, this was not the case for disfavored children who directed higher rates of

ToM-in-Action towards their younger siblings. Why might this be? Several different

theories may explain our pattern of results.

Firstly, the current study findings can be explained through the lens of Social

Learning Theory (Bandura, 1977). As described earlier, an individual may replicate

behavior patterns he or she observes occurring in the family. Perhaps, favored children

who witness their mother consistently directing more negativity toward their disfavored

sibling may replicate this dynamic when they interact with that sibling. Similarly,

disfavored children who observe their mother directing much sensitivity and positivity

toward their favored sibling, may imitate this relationship dynamic when interacting with

that sibling.

24

Secondly, our findings may suggest the presence of a partner effect within family

dynamics (i.e., siblings and mother-child interactions). A partner effect as used in Social

Relations Models, (SRM; Kenny & La Voie, 1984), refers to the degree to which an

individual elicits certain behaviours from a variety of people he or she interacts with.

SRM allows researchers to examine the family system at the family, dyad, and

individual levels to provide information on factors that impact family functioning. Thus,

disfavoured children may elicit less sensitive behaviour from their mothers and less

cognitive sensitivity and perspective taking language from their siblings. In contrast,

favoured children may pull more sensitive responding from their mother and more

cognitive sensitivity and perspective taking from their disfavored siblings. As was

discussed earlier, differential parenting can be child driven, specifically, children who

present more negative affectivity, aggressiveness and irritability, are more likely to

receive more negative treatment (Pike et al., 1996; Jenkins, Rasbash, & O‟Connor,

2003). For example, perhaps favored younger siblings who pull more cognitive

sensitivity and perspective taking from their older disfavored siblings are in fact, less

skilled and in need of more assistance when completing a challenging task. Their low

levels of ability require greater responsivity when interacting with their mothers as well.

To very briefly explore this possible explanation, bivariate correlations were conducted

to assess whether younger siblings‟ aggression, externalizing behavior, and emotional

problems may be related to levels of differentiation (for a detailed explanation of the

methods of data collection and the scales used see Meunier, Bisceglia, & Jenkins,

2012) . These measures were not found to be significantly correlated with differential

sensitivity. Perhaps other child characteristics that have not been looked at may

influence this relationship.

25

Future research should consider examining a wider array of both children‟s

characteristics in order to further explore potential “partner effects” in explaining this

pattern of results.

Lastly, the current investigation results are consistent with Hughes and

colleagues (2005) hypothesis that in families where differentiation exists, children, who

are particularly sensitive to minor inequalities within the family, are likely to engage in

conflicts and discussions with parents regarding preferred treatment. In turn, these

discussions may enhance children‟s ability to differentiate between different people‟s

perspectives. This hypothesis relied on findings that showed that in families where

conflicts were frequently discussed, children presented with accelerated ToM ability

(Dunn & Slomkowski, 1992). Even though current investigation findings did not indicate

that disfavoured siblings present with better ToM, they indeed suggest that disfavoured

siblings present with more advanced ToM-in-Action skills compared with their favoured

siblings.

The relationship between children‟s ToM-in-Action performance, as part of a

sibling interaction, and differential parenting may be mediated by other familial

processes as suggested in the aforementioned theories of Social Learning and Social

Relations Model. Therefore, these findings may be limited to the sibling dyad and

cannot be generalized to relationships and interactions outside the family unit. This can

also explain why the relationship between differential sensitivity and ToM was not

statistically significant in this study. ToM is a cognitive construct that is measured

independently from any family dynamic and thus, is less likely to be impacted by familial

interactions.

26

Our findings highlight the link between maternal sensitivity and children‟s

cognitive sensitivity. This is consistent with findings that show the relationship between

mother‟s mind-mindedness and children‟s social cognition (e.g., Meins et al., 2002). For

ToM understanding, our results showed that its strongest predictor was age, which

accounted for 22% of the variance. This is consistent with results obtained by other

researchers (e.g., Wellman et al., 2001). Age was found to be a significant predictor of

cognitive sensitivity as well, and may be indicative of the complexity of cognitive

sensitivity skills, which require the child to exhibit an integration of several prosocial

skills. Further, child language skills were shown to be significant predictors of ToM and

of perspective taking. Language has previously been shown to play a central role in the

development of ToM (Astington & Jenkins, 1999). Additionally, both ToM false-belief

tasks and perspective taking measure are highly language loaded tasks (i.e., to score

well requires adequate language skills). Interestingly, language was not found to be a

significant predictor of cognitive sensitivity. Perhaps, children who could compensate for

their low language skills by effectively using non-verbal gestures in providing both

instructions and feedback, and who presented much sensitivity and warmth, could have

received a high score on cognitive sensitivity. Finally, child gender was found to be a

significant predictor only of cognitive sensitivity, with girls showing higher skills in this

domain than boys.

5 Limitations

The cross-sectional design of the present study does not allow us to draw

conclusions regarding directionality of the relationship between differential parenting

and ToM-in-Action variables. Moreover, due to age constraints, younger siblings‟ ToM

27

and ToM-in-Action skills were not investigated. Thus, we cannot speak to the role of

birth order or dyad gender constellation in the relationship between differential parenting

with ToM and ToM-in-Action.

Finally, we did not have enough resources to observe all children within each

family, nor the fathers‟ interactions with each of their children. This can result in

misrepresentations of family dynamics in larger families (>2 children). Particularly, as

larger households were found to promote ToM skills (false-belief understanding; Jenkins

& Astington, 1996). Future research should go beyond a non-trivial sample of 372

children, and include additional family members and use longitudinal methods if at all

possible.

In conclusion, future research should focus on examining potential mediators

such as sibling relationships and partner effect, preferably within a multi-level,

longitudinal study design which will allow investigating causality and within-family

dynamics more thoroughly. It should be noted however, that while the current study

should be replicated and expanded, financial and human resources demands of such a

study would be substantial.

Despite these limitations, the current study provides useful insights about the role

of differential parenting in ToM and ToM-in-Action. Interestingly, for these outcomes

differential parenting seems detrimental for children who are favored by their parents.

This contributes yet another piece to the puzzle of the role of differential parenting in

children‟s outcomes.

28

6 References

Aguilar, B., O‟Brien, K. M., August, G. J., Aoun, S. L., & Hektner, J. M. (2001). Relationship quality of aggressive children and their siblings: A multi-informant, multimeasure investigation. Journal of Abnormal Child Psychology, 29, 479– 489.

Aiken, L., & West, S. G. (1991). Multiple regression: Testing and interpreting interactions. Newbury Park, CA: Sage.

Allison, P. D. (2003). Missing data techniques for structural equation modeling. Journal of Abnormal Psychology, 112, 545-557.

Astington, J. W., Harris, P. L., & Olson, D. R. (1988). Developing theories of mind. Cambridge: Cambridge University Press.

Astington, J.W., & Jenkins, J.M. (1995). Theory of mind development and social understanding. Cognition & Emotion, 9, 151–165.

Astington, J. W., Pelletier, J., & Homer, B. (2002). Theory of mind and epistemological development: The relation between children's second-order false-belief understanding and their ability to reason about evidence. New Ideas in Psychology, 20(2), 131-144.

Astington, J. W., & Jenkins, J. M. (1999). A longitudinal study of the relation between language and theory of mind development. Developmental Psychology, 35, 1311 – 1320.

Baron-Cohen S., Leslie A.M., & Frith U. (1985). Does the autistic child have a “theory of mind”? Cognition, 21 (1), 37-46

Bandura, A. (1977). Social learning theory. Englewood Cliffs, NJ: Prentice Hall.

Bigelow, A. E., & Dugas K. (2009). Relations Among Preschool Children's Understanding of Visual Perspective Taking, False Belief, and Lying. Journal of Cognition and Development, 9 (4), 411-433

Bowlby, J. (1982). Attachment and loss: Retrospect and prospect. American Journal of Orthopsychiatry, 52(4), 664-678.

Boyle, M. H., Jenkins, J. M., Georgiades, K., Cairney, J., Duku, E., & Racine, Y. A. (2004). Differential-maternal parenting behavior: Estimating within- and between-family effects. Child Development, 75, 1457–1476

Brody, G. H., Stoneman, Z., & McCoy, J. (1992). Parental differential treatment of siblings and sibling differences in negative emotionality. Journal of Marriage and Family, 54(3), 643-651.

29

Browne, D., T., Meunier, J., C., O‟Connor, T., G., & Jenkins, J., M. (2012). The role of parental personality traits in differential parenting. Journal of Family Psychology, 26(4), 542-553.

Burt, S., McGue, M., Iacono, W. G., & Krueger, R. F. (2006). Differential parent-child relationships and adolescent externalizing symptoms: Cross-lagged analyses within a monozygotic twin differences design. Developmental Psychology, 42(6), 1289-1298.

Carpendale, J. E. M., & Lewis, C. (2004). Constructing an understanding of mind: The development of children‟s understanding of mind within social interaction. Behavioral and Brain Sciences, 27, 79–150.

Carpendale, J. E. M., & Lewis, C. (2006). How children develop social understanding. Oxford: Blackwell.

Caspi, A., Moffitt, T. E., Morgan, J., Rutter, M., Taylor, A., Arseneault, L., Polo-Tomas, M. (2004). Maternal expressed emotion predicts children‟s antisocial behavior problems: Using monozygotic-twin differences to identify environmental effects on behavioral development. Development Psychology, 40, 149 –161

Charman, T., Ruffman, T., & Clements, W. (2002). Is there a gender difference in false belief development? Social Development, 11, 1–10.

Cole, K., & Mitchel, P. (1998). Family Background in relation to deceptive ability and understanding of the mind. Social Development, 7, 181-197.

Cole, K., & Mitchel, P. (2000). Siblings in development of executive control and a theory of mind. British Journal of Developmental Psychology, 18, 279-295.

Cutting, A. L., & Dunn, J. (1999). Theory of mind, emotion understanding, language, and family background: Individual differences and interrelation. Child Development, 70, 853-865.

Davis-Unger, A. C., & Carlson, S. M. (2008). Development of teaching skills and relations to theory of mind in preschoolers. Journal of Cognition and Development, 9(1), 26-45.

Deater-Deckard, K., Pylas, M., & Petrill, S. (1997). The Parent-child interaction system (PARCHISY). London: Institute of Psychiatry.

Dekovic´, M., & Gerris, J. R. M. (1994). Developmental analysis of social cognitive and behavioral differences between popular and rejected children. Journal of Applied Developmental Psychology, 15, 367–386.

Denham, S. A. (1986). Social cognition, prosocial behavior, and emotion in preschoolers: Contextual validation. Child Development, 57, 194–201.

30

Denham, S. A., Blair, K. A., DeMulder, E., Levitas, J., Sawyer, K., Auerbach-Major, A., et al. (2003). Preschool emotional competence: Pathway to social competence? Child Development, 74, 238–256.

Denham, S. A., Caverly, S., Schmidt, M., Blair, K., DeMulder, E., Caal, S., et al. (2002). Preschool understanding of emotions: Contributions to classroom anger and aggression. Journal of Child Psychology and Psychiatry, 43, 901–916.

Deutsch, M. (1985). Distributive justice: A social psychological perspective. New Haven, CT: Yale University Press.

Dodge, K. A. (2006). Translational science in action: Hostile attributional style and the development of aggressive behavior problems. Development and Psychopathology, 18, 791–814.

Dunn, J., & Slomkowski, C. (1992). Conflict and the development of social understanding. In C. Shantz & W. Hartup (Eds.), Conflict and development (pp. 70 – 92). Cambridge, England: Cambridge University Press

Dunn, J., Stocker, C. M., & Plomin, R. (1990). Nonshared experiences within the family: Correlates of behavior problems in middle childhood. Development and Psychopathology, 2, 113–126.

Farrant, B., M., Devine, T., J., Maybery, M., T., & Fletcher, J. (2011). Empathy, Perspective Taking and Prosocial Behaviour: The Importance of Parenting Practices. Infant and child development, 21(2), 175-188.

Fenning, R. M., Baker, B. L., and Juvonen, J. (2011). Emotion discourse, social cognition, and social skills in children with and without developmental delays. Child Development, 82(2), 717-731.

Festinger, L. (1954). A theory of social comparison processes. Human Relations, 7, 117–140.

Fonagy, P., Redfern, S., & Charman, T. (1997). The relationship between belief-desire reasoning and a projective measure of attachment security (SAT). British Journal of Developmental Psychology, 15, 51–61.

Gopnik, A., & Wellman, H. (1994). The „„theory theory‟‟. In L. Hirschfield & S. Gelman (Eds.), Domain specificity in culture and cognition (pp.257–293). New York: Cambridge University Press

Happe´, F. (1995). The role of age and verbal ability in the theory of mind task performance of subjects with autism. Child Development, 66, 843–855.

Harwood, M. D., & Farrar, M. J. (2006). Conflicting emotions: The connection between affective perspective taking and theory of mind. British Journal of Developmental Psychology, 24, 401–418.

31

Hoffman, M. L. (1984). Interaction of affect and cognition in empathy. In Izard C. E., Kagan, J., & Zajonc, R. B. (Eds.) Emotion, Cognition, and Behavior, (pp.103-131). New York: Cambridge University Press.

Holmes, H., A., Black, C., & Miller, S., A., (1996). A cross-task comparison of false belief understanding in Head Start population. Journal of Experimental Child Psychology, 63, 263-285.

Howes, C., & Matheson, C. (1992). Sequences in the development of competent play with peers: social and social pretend play. Developmental Psychology, 28, 961-974.

Hughes, C., & Cutting, A. L. (1999). Nature, nurture, and individual differences in early understanding of mind. Psychological Science, 10(5), 429-432.

Hughes, C., Deater-Deckard, K. & Cutting, A. L. (1999) “Speak roughly to your little boy?” Sex differences in the relations between parenting and preschoolers‟ understanding of mind. Social Development 8, 143–160.

Hughes, C., & Dunn, J. (1998). Understanding mind and emotion: Longitudinal associations with mental‐state talk between young friends. Developmental Psychology, 34(5), 1026–1037.

Hughes, C., & Ensor, R. (2005). Theory of mind and executive function: A family affair? Developmental Neuropsychology, 28, 645–668.

Hughes, C., Jaffee, S R., Happe´ F., Taylor A., Caspi A., & Moffitt T. E. (2005). Origins of individual differences in Theory of Mind: From nature to nurture? Child Development, 76(2), 356-370

Hughes, C., & Leekam, S. (2004). What are the links between Theory of Mind and social relations? Review, reflections and new directions for studies of typical and atypical development. Social Development, 13(4), 590-619.

Fernyhough, C. (2008).Getting Vygotskian about theory of mind: Mediation, dialogue, and the development of social understanding. Developmental Review 28, 225–262

Fonagy, P., Steele, M., Steele, H., Moran, G. S., & Higgitt, A. C. (1991). The capacity for understanding mental states: The reflective self in parent and child and its significance for security of attachment. Infant Mental Health Journal, 12(3), 201-218.

Jenkins, J. M., & Astington, J. W. (1996). Cognitive factors and family structure associated with theory of mind development in young children. Developmental Psychology, 32, 70-78.

Jenkins, J., M., Rabash, J., O‟Connor, T., G. (2003). The role of shared family context in differential parenting. Developmental Psychology,39, 99–113.

32

Kenny, D. A., & La Voie, L. (1984). The Social Relations Model. In L. Berrowitz (Ed.),

Advances in experimental social psychology (Vol. 18, pp. 142-182). San Diego, CA: Academic Press.

Kowal, A. K., Kramer, L., Krull, J. L., & Crick, N. R. (2002). Children‟s perceptions of the fairness of parental preferential treatment and their socioemotional well-being. Journal of Family Psychology, 16, 297-306

Leslie, A. (1994). ToMM, ToBY and Agency: Core architecture and domain specificity. In L. Hirschfeld & S. Gelman (Eds.), Mapping the mind: Domain specificity in cognition and culture (pp. 119–148). Cambridge: Cambridge University Press.

Lewis, C., Freeman, N. H., Kyriakidou, C., Maridaki-Kassotaki, K. & Berridge, D. M. (1996). Social influences on false belief access: Specific sibling influences or general apprenticeship? Child Development, 67, 2930–2947.

Matias, C., Scott, S., & O‟Connor, T. G. (2006). Coding of Attachment-Related Parenting (CARP).

McHale, S. M., Updegraff, K. A., Jackson-Newsom, J., Tucker, C. J., & Crouter, A. C. (2000). When does parents‟ differential treatment have negative implications for siblings? Social Development, 9, 149–172.

Meins, E. (1997) Security of attachment and the social development of cognition. Psychology Press.

Meins, E. & Fernyhough, C. (1999). Linguistic acquisitional style and mentalising development: The role of maternal mind-mindedness. Cognitive Development 14, 363-380.

Meins, E., Fernyhough, C., Wainwright, R., Das Gupta, M., Fradley, E., & Tuckey, M.

(2002). Maternal mind-mindedness and attachment security as predictors of theory of mind understanding. Child Development, 73(6), 1715-1726.

Meins, E., Russell, J., & Clark-Carter, D. (1998). Security of attachment as a predictor of symbolic and mentalising abilities: A longitudinal study. Social Development, 7, 1–24.

Onishi, K. H., & Baillargeon, R. (2005). Do 15-month-old infants understand false beliefs? Science, 308, 255–258.

Meunier, J. C., Bisceglia, R., Jenkins, J. M. (2012). Differential parenting and children‟s behavioral problems: Curvilinear associations and mother-father combined effects. Developmental Psychology, 48 (4) , 987-1002.

Meunier, J. C., Boyle, M., O‟Connor, T. G., & Jenkins, J. M. (2013). Multilevel mediation: Cumulative contextual risk, maternal differential treatment, and children‟s behavior within families. Child Development, 00 (0), 1-22.

33

Perlman, M., & Ross, H. S. (1997). The benefits of parent intervention in children's disputes: An examination of concurrent changes in children's fighting styles. Child Development, 68(4), 690-700.

Perlman, M., & Fletcher, B. A. (2012). Hellos and how are yous: Predictors and correlates of communication between staff and families during morning drop-off in child-care centers. Early Education and Development, 23(4), 539-557.

Perner, J. (1991). Understanding the representational mind. Cambridge: MIT Press.

Perner, J., Ruffman, T., & Leekam, S. R. (1994). Theory of mind is contagious: You catch it from your siblings. Child Development, 65, 1228-1238.

Pike, A., McGuire, S., Hetherington, E. M., Reiss, D., & Plomin, R. (1996). Family environment and adolescent depressive symptoms and antisocial behavior: A multivariate genetic analysis. Developmental Psychology, 32, 590–603.

Plomin, R., & Daniels, D. (1987). Why are children in the same family so different from one another? Behavioral and Brain Sciences, 10, 1–16.

Premack, D., & Woodruff, G. (1978). Does the chimpanzee have a theory of mind? Behavioral and brain sciences, 1(4), 515-526.

Prime, H., Perlman, M., Tackett, J., & Jenkins, J. (in press, 2013). Cognitive sensitivity in sibling interactions: Development of the construct and comparison of two coding methodologies. Early Education and Development. Special Issue on the Sibling Relationship as a Context for Learning and Development.

Rauer, A.J., & Volling, B.L. (2007). Differential parenting and sibling jealousy: Developmental correlates of young adults‟ romantic relationships. Personal Relationships, 14, 351-367.

Reiss, D., Hetherington, M., Plomin R, Howe, G. W., Simmens, S. J., Henderson, S. H., O‟Connor, T. J., Bussell, D. A., Anderson, E. R., & Law, T. (1995). Genetic questions for environmental studies: Differential parenting and psychopathology in adolescence. Archives of General Psychiatry 52, 925–936

Rubin, D. B. (2003). Discussion on multiple imputation. International Statistical Review, 71(3), 619-625.

Scholte, R., Engels, R. C., de Kemp, R. A., Harakeh, Z., & Overbeek, G. (2007). Differential parental treatment, sibling relationships and delinquency in adolescence. Journal of Youth and Adolescence, 36, 661−671.

Shanahan, L., McHale, S. M., Crouter, A. C., & Osgood, D. (2008). Linkages between parents‟ differential treatment, youth depressive symptoms, and sibling relationships. Journal of Marriage and Family, 70, 480–494.

34

Singer, A.T., & Weinstein, R. (2000). Differential parental treatment predicts achievements and self-perceptions in two cultural contexts. Journal of Family Psychology, 14, 491–509.

Strauss, S., Ziv, M., & Stein, A. (2002). Teaching as a natural cognition and its relations to preschoolers' developing theory of mind. Cognitive Development, 17(3-4), 1473-1487.

Suitor, J. J., Sechrist, J., Plikuhn, M., Pillemer, K., & Pardo, S. T. (2008). Within-family differences in parent-child relations across the life course. Current Directions in Psychological Science, 17(5), 334-338.

Symons, D. K. (2004). Mental state discourse, theory of mind understanding and the internalization of self-other understanding. Developmental Review, 24, 159–188.

Symons, D. K., & Clark, S. E. (2000). A longitudinal study of mother–child relationships and theory of mind in the preschool period. Social Development, 9, 3–23.

Tamrouti-Makkink, I. D., Dubas, J. S., Gerris, J. R., & van Aken, M. A. (2004). The relation between the absolute level of parenting and differential parental treatment with adolescent siblings' adjustment. Journal of Child Psychology and Psychiatry, 45(8), 1397-1406.

Vinden, P. (1999). Children‟s understanding of mind and emotion: A multi-culture study. Cognition and Emotion, 13, 19–48

Volling, B. L., McElwain, N. L., & Miller, A. L. (2002). Emotion regulation in context: The jealousy complex between young siblings and its relations with child and family characteristics. Child Development, 73(2), 581-600.

Vygotsky, L. S. (1931/1997). Genesis of higher mental functions. In R. W. Rieber (Ed.). The collected works of L. S. Vygotsky (Vol. 4). New York: Plenum (Original work published 1931).

Wellman, H. M. (1990). The child’s theory of mind. Cambridge: MIT Press.

Wellman, H. M., Cross, D., & Watson, J. (2001). Meta-analysis of theory-of-mind development: The truth about false belief. Child Development, 72, 655–684.

Wellman, H. M., & Liu, D. (2004). Scaling of Theory-of-Mind tasks. Child Development, 75(2), 523-541.

Whiteman, S. D., McHale, S. M., & Soli, A. (2011). Theoretical perspectives on sibling relationships. Journal of Family Theory and Review, 3, 129-139.

Zervas, L., & Sherman, M. (1994). The relationship between perceived parental favoritism and self-esteem. Journal of Genetic Psychology, 155, 25–33.