Tonight with your 9 to 12 year old
The prompt
“What's the silliest thing you and a friend do together that would make no sense to anyone else?”
What to listen for
An easy, enthusiastic answer shows they've built a real private world with this friend, which is a strong sign of a secure, comfortable friendship.
If they seem a little shy sharing it, that's normal, inside jokes are personal, and being asked to explain them can feel like giving away something precious.
If they say they don't really have one, that might be worth a gentle follow-up about who they'd want that kind of silliness with.
What this tells you
Having a shared private joke with someone shows they know what real, easy closeness feels like.