Helene Arnstein, of the Child Study Association, has written a number of books about interfamilial relationships, and here she discusses exchanges between parents and baby and how they will affect his emotional growth. Typically Arnstein stresses the positive in an empathic style (an agreeable quality not to be overlooked in guides for anxiety-ridden mothers and fathers) as she investigates the needs of infants, babies, and toddlers at various developmental stages. In effect she demystifies the demanding young--from the newborn whose ""needs and tensions ebb and flow like the tides--he has no way of knowing the boundaries between ""self' and ""others""--to the older toddler who fears losing his parents' love while he copes with the simplest everyday prohibitions. Arnstein reviews constructive emotional content in feeding, soothing, reaction to family and strangers, weaning, toilet training, handling tantrums and anger, nursery school regimens, sex identity, etc. Her neo-Freudian view of the evolution of sexual attitudes and behavior may irritate some, although she deplores rigid role stereotypes and presents a quick overview of ongoing studies in inherent and culturally induced sex-related behavior. With her attention throughout to the needs of parent as well as child--a comforting if familiar guide to living with your baby.