Thanks for replying, he does know about the differences, he has an older sister, they still bath together but he has never done this to her only other girls, I have also explained the reason why doing what he is doing is not right, we have discussed why he doesn't like it etc I know it's normal sexual development for any child and I am not that worried, but I now have other parents ringing me up to tell me he has got their child to take their knickers off. I just worry that people aren't going to want him around their children...