My SS has said he did some "bad" things when he was a teen. Fortunately for me I wasn't around then.

But he really hasn't changed who he is. Just last year he went to jail for 10 days for getting into a fight with an elderly man while drunk. We refused to pay his fine. I say "we" but DH might have caved if I didn't control the money totally,

He is an alcoholic and with anger management issues. Has been for about 15 years and he's not even 30 yet. As far as I can tell he is not a thief though.

SS has never been rude or violent with me. But I have not spent time with him while he is drunk and don't intend to do so.

Kids do change. My step-daughter stole from me but I'd give her my wallet now for safe-keeping if necessary. I stole from my Dad's wallet as a kid but turned in a found wallet intact just a few years later.

It's easy enough to keep stealable things away from them until you're sure of their intentions. Or put $5 out where they can see it under circumstances that they can think you won't miss it. Peeking out from a couch cushion for instance. Then you'll know if they're trustworthy.

Punishing people for things they did as kids is stilly - even as a society we don't keep kids in jail for murder past age 24 if they were very young when they did it.

I guess it really depends. How many years ago did the theft take place?

I've been in similar situations. JFK's remark "forgive your enemies but never forget their names" comes to mind. Forgiving these people helped to free me and helped me become a happier, better person. It did not happen overnight, but it did happen. But I never forgot.