Our LO is having a party, we know that a couple of the potential invitees have unwelcome guests in the hair department. their parents are treating them, but would we be U to not invite them? They aren't part of LO's social group and if nits were to strike it would be pretty obvious where they came from, but the invitees are quite close and if we don't invite it could make other gatherings awkward.
Or do we just make it a swimming cap party?