Does he know how a woman gets pregnant because if he doesn't you will totally confuse him. My sone is 10 and he just had a sex ed course at school and they explained to him about the whole sperm thing and when he was telling me about it my 8 year old was totally confused and still asks how the sperm gets in the mommy. So, I would advise you to talk to him about sex first. If he isn't ready to learn about sex, he probably isn't ready to learn about biological parents.
at 7:22 AM on Jul. 17, 2008