The purpose of this study was to determine if sex differences were observable in 1-year-olds in response to their mother and in choice and style of play with toys. Thirty-two boys and thirty-two girls were put in separate rooms with several toys, several nontoys (door knobs, taped sockets, etc.) and their mothers. The infant's mother was to observe the child in play and respond as she desired. Observation was conducted from another room. Earlier in the study, the mother's touching behavior of the 6-month-old infant was observed. The results showed that at 1 year, boys were more independent of their mothers than were the girls, who touched their mothers and vocalized more frequently. Boys demonstrated more exploratory play and banging of toys than the sedate and quiet playing girls. It was shown that the boys' dependence was directly proportionate to the amount of touching at 6 month's old given by the mother. For girls, a curvilinear scale resulted. Girls who were touched moderately were more independent than those touched greatly or very little. It was concluded that the child's independence was influenced by the mother's behavior toward the child at an earlier age. From the results of toy play behavior, it was concluded that parents reinforced sex role behavior in the 1-year-old and later the child internalized such roles. (JS)