The reaction of first-born children to the birth of a sibling: mothers' reports.
D000367:Age Factors; D000704:Analysis of Variance; D001722:Birth Order; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009034:Mother-Child Relations; D010551:Personality; D002666:Psychology, Child; D012044:Regression Analysis; D012043:Regression, Psychology; D012737:Sex Factors; D012801:Sibling Relations; D012893:Sleep Wake Disorders / Q000453:epidemiology; D012917:Social Adjustment