Full context I've been with my DH for seven years and my DSD is 12. We've always had a few problems because she has used my stuff (an iPad a few years ago) and now my makeup without asking. I've always been clear she can use it if she asks, not just take it without permission.
This year I noticed my makeup started to disappear. Some bits are worthless but many have sentimental value (for example I still have a few bits I bought 20+ years ago and believe it or not still use them!)
I told my DH to have a chat with her. He did a few of them. Maybe about a month ago I saw she took one of those precious bits of makeup and she completely destroyed it. So I had enough and told him he had to discipline her. Up to that point we thought the matter was solved.
Until yesterday... When I found even more makeup and some newish eyeliners, including the empty box of my engagement ring. She claimed she didn't know how they appeared in her room. I knew she took them. DH wanted a clean slate, I asked him to go through her drawers and voila! More of my missing makeup. He doesn't necessarily think I'm over reacting but I hate being portrayed as the evil step mum when it's my stuff!
We have bought her tons of her own makeup. Some even came in very nice cases and she just ends up destroying it all. We actually don't know why, but she paints on the walls/paper/her bed with it.
After this last episode I'm worried she might take my jewellery too.