My son stole treasured family jewelry from me too, many years ago. Not terribly valuable but priceless because of their history.
I'm still angry about that, and it's maybe 9 years later. I don't let my anger rule me or even throw my day, I just acknowledge it and let it be and maybe one day it won't matter so much.
I think that is the difference between anger and resentments. Resentments eat away at us every day, anger is just a bad memory that reminds us to not let it happen again.
hugs