We compared language comprehension and production across the second year of life in children of clinically depressed mothers who later remitted with children of nondepressed mothers. Altogether, 157 mother-child dyads participated: 46 with mothers diagnosed at infant age 5 months as having major, minor, or other depressive disorders who fully…

We compared the structure and the content of mothers' and fathers' infant-directed speech as a function of infant birth order. Seven first-born and four second-born infants were video-recorded during their natural dyadic interactions with their mothers and fathers at home from the second to the sixth month after birth at 15-day intervals.…

This study examines the relationship between the psychological states of Korean mothers and early childhood development. In the study, 480 mothers were classified into three groups: cluster A mothers were happy and competent, cluster C were depressed and stressed, and cluster B were neither depressed nor happy. The tendency of infant developmental…

The developmental science literature is riven with respect to (a) parental similar versus different treatment of siblings and (b) sibling similarities and differences. Most methodologies in the field are flawed or confounded. To address these issues, this study employed a within-family longitudinal design to examine developmental processes of…

Longitudinal data were obtained from 157 children aged 3 years 3 months to 5 years 6 months at Time 1. At Time 2 these children had aged an average of 12 months. Theory of mind (ToM) and executive functioning (EF) were measured at both time points. Results suggest that Time 1 ToM scores predict Time 2 EF scores. Detailed examination of sibling…

This article, using longitudinal data from the National Child Development Study, presents new evidence on the effects of family size and birth order on test scores and behavioral development at age 7, 11 and 16. Sibling size is shown to have an adverse causal effect on test scores and behavioral development. For any given family size, first-borns…

This study examined siblings' teaching strategies in 72 dyads (firstborn and second born, M ages = 81.64 and 56.31 months) as a function of dyad age, age gap between siblings, and teacher birth order. One child per dyad was randomly assigned to teach her or his sibling to construct a tractor toy. Interactions were coded for the topic of teachers'…

This study charted the development of gendered personality qualities and activity interests from age 7 to age 19 in 364 first- and second-born siblings from 185 White, middle/working-class families, assessed links between time in gendered social contexts (with mother, father, female peers, and male peers) and gender development, and tested whether…