Aggression, Sibling Antagonism, and Theory of Mind During the First Year of Siblinghood: A Developmental Cascade Model

Siblings at home: Moderating influence of sibling presence and composition on the relation between problem behaviors and Theory of Mind in early childhood

Despite the prevalence of internalizing and externalizing difficulties in children, the impact of these problem behaviors on the development of important social cognitive skills, such as Theory of Mind (ToM), is not well-understood. Indeed, many studies that have explored relations between problem behaviors and ToM report inconsistent findings. A possible reason for these disparities may be a lack of accounting for social protective factors within the home, such as the presence and number of siblings. Here, we explored the moderating influence of sibling presence and number on the relation between problem behaviors (i.e., internalizing and externalizing) and ToM. A total of 184 children (88 boys; Mage = 64.6 months, SD = 10.39) completed six well-validated ToM tasks while mothers reported on their children's externalizing and internalizing behaviors. Children who had siblings living in the same home exhibited higher ToM than children without siblings. In addition, both sibling presence and number of siblings moderated the relation between children's externalizing behaviors and ToM, such that in children without siblings externalizing behaviors were negatively associated with ToM. In contrast, children with siblings had similar ToM regardless of externalizing behaviors. As well, children with relatively fewer siblings and higher externalizing behaviors displayed lower ToM than children with relatively more siblings and higher externalizing behaviors. We did not detect a moderating effect of sibling presence or number on the relation between internalizing behaviors and ToM. These findings provide support for siblings' protective utility within the context of children's social cognition.

Sibling bullying victimization and subjective well-being among children across 13 countries: The mediating roles of perceived social support and the moderating role of uncertainty avoidance culture

BACKGROUND

While sibling bullying victimization has been recognized as a significant factor detrimentally impacting children's subjective well-being, the underlying mechanisms have yet to be fully elucidated.

OBJECTIVE

This study seeks to investigate the potential mediating role of perceived social support, encompassing support from family, friend, teacher, and neighbor, as well as the moderating influence of uncertainty avoidance culture.

PARTICIPANTS AND SETTING

A sample of 19,328 children was obtained from Wave Three of Children's Worlds: International Survey of Children's Well-being in 13 countries.

METHODS

The structural equation model (SEM) was used to investigate the mediating role of perceived social support in the relationship between sibling bullying victimization and children's subjective well-being. The multiple group analysis was carried out to assess the moderating role of uncertainty avoidance culture.

RESULTS

This study reveals a negative association between sibling bullying victimization and children's subjective well-being (β = -0.138, p < 0.001). Perceived support from family, friend, teacher, and neighbor emerges as a mediating mechanism in this relationship. Uncertainty avoidance culture moderates this relationship, and this association is stronger for children raised in a strong uncertainty avoidance culture (β = -0.085, p < 0.001).

CONCLUSIONS

The results of this study contribute to our comprehension of the nexus between sibling bullying victimization and children's subjective well-being. Moreover, this study extends the current body of knowledge by delving into the cultural disparities spanning various countries.

The relation between aggression and theory of mind in children: A meta-analysis

Previous findings on the association between theory of mind (ToM) and aggression in children are mixed. The social skills deficit view regarded ToM as a single-edged sword and proposed that a lack of ToM can lead to aggression, while the double-edged sword view proposed that children with advanced ToM can still show much aggression because children can also leverage ToM to harm others. To resolve the dispute between the two views, we conducted a meta-analysis combining cross-sectional and longitudinal findings from 53 studies including a total of 11,579 children aged between 2 and 15 years. The overall negative correlation between ToM and aggression was small but significant (r = -0.08). The negative correlation was robust, with the magnitude of the correlation being similar across physical versus relational aggression, proactive versus reactive aggression, cognitive versus affective ToM, preschoolers versus school-aged children, different aggression measurements, and different levels of societal individualism. Moreover, the negative correlation was found regardless of whether ToM and aggression were measured concurrently or at different time points, but the correlation was the largest when ToM was measured before aggression. Whether the aggression was bullying or not also moderated the association, with ToM only being negatively related to non-bullying aggression but not bullying. Together, these findings suggest that ToM is a single-edged sword to decrease general aggression and that aggression might also give rise to lower ToM capacity during development. RESEARCH HIGHLIGHTS: This study systemically reviewed the existing mixed findings on the association between aggression and ToM during childhood using a meta-analysis. There was a negative correlation between ToM and aggression in children aged between 2 and 15 years. The negative correlation between aggression and ToM was stronger when ToM was measured first, followed by aggression, than vice versa. There was a negative correlation between non-bullying aggression and ToM, whereas there was no correlation between bullying and ToM.

"A pirate goes nee-nor-nee-nor!" humor with siblings in middle childhood: A window to social understanding?

Humor is a central feature of close and intimate relationships in childhood. However, fundamental questions regarding the relationship between humor production, pretend play, and social understanding have been overlooked. In a selected subsample from a prospective longitudinal study of first-born children (N = 110, M age = 6.91 years, 46.4% female, 98.1% parents identified as English, Welsh, Scottish, or Irish), we conducted detailed observational coding of children's humor production during dress-up play with younger siblings. Focal children also completed a battery of social understanding tasks that measured emotion understanding and second-order belief understanding. Focal children were also observed during solo free play with Playmobil, and their spontaneous references to others' cognitions and play with objects were coded. Correlation analyses indicated that children's word play with their sibling was associated with their tendency to engage in pretense during solo play. Regression analyses showed that humorous sound play with siblings was associated with their emotion understanding and playful teasing with siblings was associated with their spontaneous references to others' cognitive states during solo free play. Our findings contribute to knowledge and theory regarding domains of development associated with humor production in childhood. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Transition to siblinghood causes a substantial and long-lasting increase in urinary cortisol levels in wild bonobos

In animals with slow ontogeny and long-term maternal investment, immatures are likely to experience the birth of a younger sibling before reaching maturity. In these species, the birth of a sibling marks a major event in an offspring’s early life as the older siblings experience a decrease in maternal support. The transition to siblinghood (TTS) is often considered to be stressful for the older offspring, but physiological evidence is lacking. To explore the TTS in wild bonobos, we investigated physiological changes in urinary cortisol (stress response), neopterin (cell-mediated immunity), and total triiodothyronine (T3, metabolic rate), as well as changes in behaviors that reflect the mother–offspring relationship. Following a sibling’s birth, urinary cortisol levels of the older offspring increased fivefold, independent of their age, and remained elevated for 7 months. The cortisol level increase was associated with declining neopterin levels; however, T3 levels and behavioral measures did not change. Our results indicate that the TTS is accompanied by elevated cortisol levels and that this change does not coincide with nutritional weaning and attainment of physical independence. Our results suggest that bonobos and humans experience TTS in similar ways and that this developmental event may have emerged in the last common ancestor.

Siblings' Perspectives of the Impact of Child Sexual Abuse Disclosure on Sibling and Family Relationships

Child sexual abuse (CSA) may have significant consequences for siblings; however, limited research has been conducted on the impact of the abuse on sibling and family relationships following the disclosure of CSA. This study sought to investigate sibling responses to disclosures of CSA among a group of adult siblings in Ireland, and the impact on sibling and family relationships through an online survey. A thematic analysis was conducted on a sub-set of participants who responded to open-ended questions (n = 45). Three main themes were identified as follows: (a) intense emotional reactions, (b) relationship support and strain, and (c) managing family dynamics. CSA disclosure may have a substantial impact on sibling and family relationships. Supporting siblings in the aftermath of CSA disclosure is essential, both for the well-being of the individual who was sexually abused and for the wider family.

Viewing Development Through the Lens of Culture: Integrating Developmental and Cultural Psychology to Better Understand Cognition and Behavior

Although many definitions of culture exist, studies in psychology typically conceptualize different cultures as different countries. In this article, we argue that cultural psychology also provides a useful lens through which to view developmental milestones. Like other forms of culture, different developmental milestones are demarcated by shared values and language as well as transmission of particular social norms. Viewing development through the lens of cultural psychology sheds light on questions of particular interest to cultural psychologists, such as those concerning the emergence of new cultures and the role of culture in shaping psychological processes. This novel framework also clarifies topics of particular interest to developmental psychology, such as conflict between individuals at different milestones (e.g., arguments between older and younger siblings) and age-related changes in cognition and behavior.

A Reciprocal and Dynamic Development Model for the Effects of Siblings on Children's Theory of Mind

In the field of social influences on Theory of Mind (ToM), more research has focused on the role of parents, but less research has examined the impact of siblings on children’s social understanding. We review existing research related to what factors might affect sibling–ToM association and how these potential factors affect ToM. Based on the literature review, we propose an integrative model that unites three categories of factors (i.e., sibling structural variables, sibling individual variables, parental intervening variables) that might have effects on the sibling–ToM association and highlights mental-state talks during sibling interactions at the intersection of sibling-related variables and ToM. Furthermore, we propose some issues arising from this review that need to be clarified in future studies. Specifically, we hope to clarify the specific effects of older and younger siblings on children’s understanding of human minds, the similarities and differences of sibling–ToM association under different cultural backgrounds, and the impact of family social disadvantage (e.g., lower SES) on the sibling–ToM association. All these works would benefit from the verification, revision, and expansion of our reciprocal influence model for the sibling–ToM association.

Early pathways to bullying: A prospective longitudinal study examining the influences of theory of mind and social preference on bullying behaviour during the first 3 years of school

Research has focused on the role of theory of mind (ToM) for positive social behaviour, while the association between ToM and negative social behaviours is less well understood. This longitudinal study compares two mediation models examining the role of ToM and peer-rated social preference at ages 5 and 6 for bullying at age 7. Participants were 114 children (58 boys, M_age  = 67 months) at entry to primary school (T1). At Time 2 (T2), 106 children and, at Time 3 (T3), 96 children remained. Teacher-rated externalizing problems and children's language ability were controlled at T1. Poor ToM was found to indirectly predict later bullying via poor social preference, while for boys only, greater earlier ToM directly predicted greater bullying 2 years later. These results suggest that there are different pathways to bullying via ToM and social preference, which has implications for interventions to prevent the development of bullying behaviour.

Family structure, birth order, and aggressive behaviors among school-aged boys with attention deficit hyperactivity disorder (ADHD)

PURPOSE

To evaluate the associations between family structure, birth order, and aggressive behaviors among school-aged boys with attention deficit hyperactivity disorder (ADHD).

METHODS

We conducted a matched case-control study. Data were retrieved from medical records at a psychiatry center in northern Taiwan. School-aged boys with ADHD who first visited the outpatient department at the psychiatric center between 2000 and 2011 were identified. The Child Behavior Checklist was used for aggressive behavior assessment. Boys with ADHD with T scores higher than 70 on the aggressive subscale were classified as cases and others with T scores lower than 70 were classified as controls at a 1:4 ratio. After controlling for other familial, personal, and parental factors, a multivariate conditional logistic regression was performed to evaluate the effects of family structure and birth order on aggressive behaviors of boys with ADHD.

RESULTS

277 cases and 1108 controls were included in the final analysis. Compared with living in a traditional family with both parents, living in a non-traditional family in which one or both parents were absent increased the risk of aggressive behaviors by 1.47-fold, with the highest risk for those in single parent families. Being the firstborn increased risk by 1.45-fold and the risk was higher when the firstborn had siblings.

CONCLUSIONS

Living in non-traditional families in which one or both parents were absent, and being the firstborn increased risk of aggression in school-aged boys with ADHD. Identification of this high-risk population and development of adequate preventive strategies are warranted.

Sibling bullying at 12 years and high-risk behavior in early adulthood: A prospective cohort study

Emerging evidence suggests that sibling aggression is associated with the development of high-risk behavior. This study investigated the relationship between sibling bullying perpetration and victimization in early adolescence and high-risk behavior in early adulthood. Sibling bullying was assessed at 12 years in 6,988 individuals from the Avon Longitudinal Study of Parents and Children, a birth cohort based in the UK and high-risk behavioral outcomes were assessed at 18-20 years. Frequent sibling bullying perpetration predicted antisocial behavior (OR = 1.74; 95%CI, 1.38-2.20), while frequent sibling bullying victimization increased the odds of nicotine dependence (OR = 2.87; 95%CI, 1.55-5.29), even after accounting for peer bullying and parent maltreatment. Categorical analysis revealed that particularly bullies and bully-victims were at risk of developing high-risk behavior. Finally, this study found that adolescents who were involved in bullying perpetration across multiple contexts (home and school) had the highest odds of reporting antisocial behavior (OR = 3.05; 95%CI, 2.09-4.44), criminal involvement (OR = 2.12; 95%CI, 1.23-3.66), and illicit drug use (OR = 2.11; 95%CI, 1.44-3.08). Findings from this study suggest that sibling bullying perpetration may be a marker of or a contributory factor along the developmental trajectory to antisocial behavior problems. Intervention studies are needed in order to test whether reducing sibling bullying can alleviate long-term adverse social and behavioral outcomes.

Revisiting the famous farm foxes: A psychological perspective

Five decades ago, Dmitry Belyaev, Lyudmila Trut, and colleagues began a now-famous experiment, selectively breeding foxes based on one criterion: perceived tame behavior. Over generations, the fox population changed in behavior (as predicted) but, intriguingly, also changed markedly in appearance-for example, many had wider mouths, curlier tails, different fur coloring, and floppy ears. These researchers concluded that the morphological changes that appeared in their foxes were a by-product of the researchers' selecting for genetic variants that are implicated both in behavior and in appearance. For decades, scientists have largely accepted this "shared genetic variants" interpretation to fully account for the co-occurrence of behavioral and morphological phenotypes in these foxes and in other domesticated animals. However, several decades of psychological research on human social cognition, human-canine interaction, and canine behavior strongly suggest that such an account may be incomplete. I forward a supplementary perspective, based on psychological research, that the covariation of appearance and behavior among these foxes may be partly an artifact of human psychological processes at play in selection. These processes include humans' tendency to infer individuals' traits based on their physical features; trait inferences, in turn, influence how humans treat those individuals. If accurate, this account bears on our understanding of these famous foxes, human-canine interactions, as well as humans' role in domestication.

A Systematic Review of Theory of Mind’s Precursors and Functions

Abstract. We conducted a systematic review of longitudinal theory of mind (ToM) studies, focusing on the precursors to and functional outcomes of ToM in typically-developing samples. Our search yielded 87 longitudinal studies, all of which involved children and adolescents. Early attention skills, executive function development, and the use of language are precursors to ToM development. Additionally, quality interaction with parents and older siblings can foster early improvements in ToM. Healthy ToM development improves social relationships with peers and produces greater desire to engage in prosocial behaviors. However, victimized individuals with highly-developed ToM may engage in increased aggression. Future longitudinal research is needed to investigate the functional outcomes resulting from ToM changes in adulthood.

Theory-of-Mind Development and Early Sibling Relationships after the Birth of a Sibling: Parental Discipline Matters

This study investigated relations among children's Theory-of-Mind (ToM) development, early sibling interactions, and parental discipline strategies during the transition to siblinghood. Using a sample of firstborn children and their parents (N = 208), we assessed children's ToM before the birth of a sibling and 12 months after the birth, and sibling interactions (i.e., positive engagement and antagonism) and parental discipline strategies (i.e., child-centred and parent-centred discipline) at 4 and 8 months in the first year of siblinghood. Structural equation modelling analyses revealed that children's ToM before the birth of the sibling predicted children's positive engagement with the infant sibling, whereas children's antagonistic behaviours towards the infant sibling negatively predicted children's ToM at 12 months, but only when mothers used low levels of child-centred discipline. These findings emphasize the role of parents in the development of young children's social- cognitive understanding in the context of sibling interactions even as early as the first year after the sibling's birth.

Longitudinal reciprocity between theory of mind and aggression in middle childhood

Theory of mind is one of the most important cognitive factors in social information-processing, and deficits in theory of mind have been linked to aggressive behavior in childhood. The present longitudinal study investigated reciprocal links between theory of mind and two forms of aggression – physical and relational – in middle childhood with three data waves over 3 years. Theory of mind was assessed by participants’ responses to cartoons, and physical and relational aggression were assessed through teacher reports in a community sample of 1657 children (mean age at Time 1: 8 years). Structural equation modeling analyses showed that theory of mind was a negative predictor of subsequent physical and relational aggression, both from Time 1 to Time 2 as well as from Time 2 to Time 3. Moreover, relational aggression was a negative predictor of theory of mind from Time 1 to Time 2. There were no significant gender or age differences in the tested pathways. The results suggest that reciprocal and negative longitudinal relations exist between children’s theory of mind and aggressive behavior. Our study extends current knowledge about the development of such relations across middle childhood.