Drives and knowledge. A speculation.
D000223:Adaptation, Psychological; D002657:Child Development; D003071:Cognition; D004328:Drive; D004777:Environment; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007398:Interpersonal Relations; D009034:Mother-Child Relations; D009042:Motivation; D011574:Psychoanalytic Theory