This longitudinal study - conducted in the Midwestern United States - examines the child-level factors that promote Spanish-English bilingual toddlers' (n = 47; M[subscript age] = 18.80 months; SD[subscript age] = 0.57) productive vocabulary skills from 18 to 30 months of age. At 6-month intervals, caregivers reported on toddlers' Spanish and…

Friends are a vital source of social relations throughout the lifespan and across developmental stages. Our knowledge of how friendships develop over time, especially from childhood through adulthood, is limited. Furthermore, it is now recognized that this specific type of relationship influences health across the life course in unique ways. Using…

A foundational mechanism underlying human cooperation is reciprocity. In the context of repeated interactions with others, it is not always clear the degree to which in-kind responses reflect responsiveness to partners' prior behaviors ("reactive" responses), an interest unrelated to the partner ("nonreactive" responses), or…

This study examined parental romantic attachment security as a mediator of prospective associations between hostile interparental conflict and parental discipline (i.e., power-assertive, permissive, and inductive discipline) for mothers and fathers of young children. Furthermore, this study utilized a novel, automatic assessment of romantic…

Children show less positivity toward gender-nonconforming (GN) than gender-conforming (GC) peers. Yet, little is known about children's reasoning about peers of varying gender expressions, including age-, gender-, and culture-related influences. We investigated how children aged 4- to 5- and 8- to 9-years-old in Hong Kong and Canada (N = 678)…

Gender and age are salient social categories from early in development. However, whether children's beliefs about gender and age intersect, such that gender stereotypes might be expressed differently when asked about children (compared to adults) has not been investigated. Here, in a preregistered study (N = 297), we examined if young children…

Can well-documented gender differences in evaluations of prosocial versus antisocial actions found in childhood and adulthood be traced to sex differences in basic sociomoral preferences in infancy? We provide an answer to this question by meta-analyzing sex differences in preference for prosocial over antisocial agents in a set of 53 samples of…

Existing research focused on social role destabilization (historical increases in role instability) and destandardization (historical increases in variability of role instability) has primarily focused on discrete social roles during discrete periods of development. Building on this work, we applied a macro approach to elucidate the extent to…

Adolescence and emerging adulthood is likely a sensitive period for the neural effects of stress due to increasing life stress, onset of stress-related disorders, and continued gray matter (GM) development. In adults, stress is associated with GM differences in the medial prefrontal cortex (mPFC), hippocampus, and amygdala, but little is known…

We leveraged nationally representative data from the Panel study of Income Dynamics-Child Development Supplement (N = 3,562) and the Early Childhood Longitudinal study (N = 18,174), to chart the development of working memory, indexed via verbal forward and backward digit span task performance, from 3 to 19 years of age. Results revealed nonlinear…

Theory and research highlight the mismatch between puberty-associated challenges and personal coping resources among youth with early actual or perceived pubertal timing. This study (N = 167; M[subscript age] = 12.41 years; 51.5% female; 77.8% White American) examined whether coping resources provided by mothers (maternal socialization of coping)…

Self- and group orientations represent distinct ways of perceiving the relations between the world and the self and are relevant to adolescents' development. Most of the existing studies in this area are cross-sectional, providing little information about how self- and group orientations develop. This 3-year longitudinal study examined the…

This study synthesizes theories of achievement motivation to better understand the development of academic task values in high school students and their relation to college major selection. We utilize longitudinal structural equation modeling to understand how grades relate to task values, how task values across domains relate to one another over…

Data from 83,423 parent reports of temperament (surgency, negative affectivity, and regulatory capacity) in infants, toddlers, and children from 341 samples gathered in 59 countries were used to investigate the relations among culture, gender, and temperament. Between-nation differences in temperament were larger than those obtained in similar…

Drawing on the situated expectancy-value, dimensional comparison theories, and the intersectionality approach, this article examined the changes in adolescents' math and science motivational beliefs, the parental and college correlates of those beliefs, and the differences at the intersection of gender and college generation status (i.e., female…