Pre-teens and teens need to know that deciding whether or not to masturbate is a personal choice that may depend upon the values of their family. Sexual feelings can be cause for great concern. It is for this reason that simple and accurate information about the body and its functions should be presented. They must know how to have relationships without getting hurt and without hurting others. Amazingly enough, between birth and 18 months, children begin to develop their identity as either female or male. They need to know that they are not alone in their self-doubts and fears. It usually takes about years to get through puberty.