my son used to kindof scratch at his penis, either inside his pants or through his clothes. It drove my husband (a pediatrician) crazy!!!!!!!!(husb would say "he can't just keep doing that or he'll be standing in front of class doing it during presentations in HIGH school")
Needless to say, my husb was more onto this behavior than I was, and our son told a friend "my dad told me not to touch my penis".....but sons sexuality really seems OK ....... For awhile, I think age 4 and 5, the
behavior seemed to continue even when we tried to stop it and now has just died down, he's almost 8.
My favorite thing to say was, "that's private" and tell him not to do it while watching TV, etc.