Used prospective longitudinal design to ascertain whether different types of behavioral inhibition were stable from toddler to preschool age, and whether inhibited temperament or parenting style predicted children's subsequent social/behavioral problems. Found that traditional and peer-social toddler inhibition predicted socially reticent behavior at age four. Maternal behaviors moderated the relation between toddlers' peer inhibition and preschoolers' social reticence. (Author/KB)