Not sure if this is exactly the right place but figured it would get the most traffic. Apologies if it goes on a bit too, I'll explain...
A few months ago DD (4.8) and DN (7) were playing upstairs at a family party. My mum overheard DN say to DD "Lets play the Willy Game, I'll show you my willy and you can touch it". DD said thats a silly game or something and then mum went in and asked them to come downstairs to play. I mentioned it to SIL so she could have a word with DN and explain that its a silly game and not something he should do. Was a bit awkward but she had a word. I told DD that we don't play games like that and if it happened again to tell em or DH.
They have played together several times since and DN always wants to play with DD on his own, and won't let DS join in but I figure this is more than likely because DS can be a PITA. Anyhow, yesterday we were at FIL, and they were playing upstairs and in the dinning room on their own (we were in the lounge), DN kept asking me to not let DS play with them. DH thought it a bit odd as they weren't playing anything specific just pretending games. Anyway last night DD was saying what a fun time she had had playing and then started giggling about the silly games she was playing with DN. So I asked what they were playing. She said they played Doctors and DN told her to lie down, took off her knickers and wiped and touched her ladybum (apologies thats what we call it). They then played the Willy game again, and he told her to look at his willy but she didn't want to touch it. DH was furious with DN. I told him I'm sure it was just childhood curiosity but he said DN was very devious and when he thought about it was constantly trying to get DD on her own. FWIW I think DH was a tad over dramatic here. DD also said that DN had asked her not tell.
I rang SIL and explained what DD told me they had been playing, and that DD wasn't allowed to tell. She just kind of laughed and said have a word but I got the impression she didn't thinkit was a big deal. I explained that I would not be letting them play on their own together in future.
Am I over-reacting? Is this normal for kids? Or is it a big deal?