After birth, the process of sex-role socialization begins immediately. There may be small, physiologically-based differences present at birth that lead girls and boys to perceive the world or behave in slightly different ways. There are also well-documented differences in the ways that boys and girls are treated from birth onward. The behavioral differences between the sexes, such as differences in toy and play preference and in the degree of aggressive behavior, are most likely the product of complex interactions between the way that the child perceives the world and the ways that parents, siblings, and others react to the child. The messages about appropriate behavior for girls and boys intensify differences between the sexes as the child grows older.
It is not uncommon for children to touch or play with their genitals or to play games, such as “doctor” or “house,” that include sexual exploration. Such experiences are usually not labeled sexual by the children. Adults will often discourage such behavior and respond negatively to it. Generally by the age of six or seven, children develop a sense of privacy and are aware of social restrictions on sexual expression.
As the first bodily changes of puberty begin, sometime from the age of 8 to the age of 12, the child may become self-conscious and more private. During this period, more children gain experience with masturbation (self-stimulation of genitals). Surveys indicate that about one-third of all girls and about half of all boys have masturbated to orgasm by the time they reach the age of 13, boys generally starting earlier than girls. Because preadolescents tend to play with others of their own sex, it is not at all uncommon that early sexual exploration and experience may happen with other members of the same sex.