DS is 4 and to be fair he does have his problems. He is very behind socially, doesn't seem to understand boundaries and not bothered about consequences.
Anyway, whenever he has a friend round or is at another friends house and they are playing alone he always ends up either taking his own pants and trousers off or encouraging the other child to.
I've never quite known what to say to this but have spoken each time about how that area is private to each person and it could upset them. How he should only show his willy to mummy, daddy or a doctor if it's poorly or play alone in his room if that's what he wants to do.
How do I tackle this? What I'm saying obviously isn't going in and as much as other parents know that its part of him growing up and learning it will get to a point where they won't want him around their children.