The first two years. Bliss or chaos.
D000342:Affective Symptoms; D000375:Aging; D002652:Child Behavior; D002657:Child Development; D002675:Child, Preschool; D002658:Developmental Disabilities; D004644:Emotions; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010287:Parent-Child Relations