In early childhood, children begin serious exploration of their bodies. It is during this period that children are usually toilet trained, and they go through a period of intense interest in their genitals and bodily wastes.
They begin to ask the first, basic questions about sex, usually about why boys and girls have different genitals and what they are for. They begin to explore what it means to be “boys” or “girls” and turn to their parents, siblings, or television for models of gender behavior. Sometimes children at this age will appear flirtatious or engage in sexual behaviors such as kissing in an attempt to understand gender roles. However, it is almost certainly wrong to suggest that these behaviors are motivated by sexual desire at this young age.