Examined the self-esteem of middleborns compared with firstborns and lastborns. Studied the number, spacing, and sex of siblings of the middleborn. Data were obtained from a national sample of over 2,200 adolescent males. Results suggested that middleborns have a significantly lower self-esteem than firstborns and lastborns. (Author)

Early personality and environmental characteristics that predict later problematic aggression and depression in children were investigated longitudinally. A developmental psychopathology approach was taken. (This approach assumes that patterns of adaptation and maladaptation in development can best be understood when explored simultaneously and…