The goals of this study were to investigate whether young children attending Head Start (N = 292; M[subscript age] = 4.3 years) selected peers based on their preschool competency and whether children's levels of preschool competency were influenced by their peers' levels of preschool competency. Children's peer interaction partners were…

Using both traditional composites and novel profiles of anger, we examined associations between infant anger and preschool behavior problems in a large, longitudinal data set (N = 966). We also tested the role of life stress as a moderator of the link between early anger and the development of behavior problems. Although traditional measures of…