Tonight with your 9 to 12 year old
The prompt
“What's something you collect or really care about that you don't think most people would get?”
What to listen for
If they light up describing it in detail, that thing is doing real work for their sense of self, it's a place where they feel fully themselves without needing anyone's approval.
If they seem a little shy or add "it's probably weird," they may need to hear clearly that liking something deeply is never something to be embarrassed about, especially at home.
If they say nothing comes to mind, that's fine, some kids find that footing in an activity more than an object, so you might hear about it in a different question.
What this tells you
This shows you where they've built a private sense of identity that's just theirs, separate from what friends or family think.