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…

We used structural equation modeling in the Early Childhood Longitudinal Study--Kindergarten Cohort (N = 17,020) to explore the influence of having an older sibling on kindergarten-age focal children's cognitive self-regulation. In model 1, we tested how having a sibling who is generally older than the focal child contributes to the focal child's…