Key points are not available for this paper at this time.
BROOKS, JEANNE, and LEwis, MICHAEL. Attachment Behavior in Thirteen-Month-Old, Opposite-Sex Twins. CHILD DEVELOPMENT, 1974, 45, 243-247. 17 sets of opposite-sex twins, 13-14 months old, were observed in a playroom situation with their mothers. Attachment behaviors, toy preference, style of play, and activity level were recorded. Analysis of 4 attachment behaviors indicated that girls looked at and maintained proximity with their mothers significantly more often than did their brothers. Girls also touched and vocalized to their mothers more
Brooks et al. (Fri,) studied this question.