He needs to realize that crossing the boundaries of privacy is unacceptable...perhaps he feels uncomfortable buying some new items of clothing himself and so resorts to stealing whatever he can find from his family. I still find it somewhat odd though. He must have realized that he would eventually be caught? Perhaps he also gets a kick from that.

The only thing you can do is state very clearly that you don't have an issue with him or his fetish but that he is simply not permitted to take items of clothing that do not belong to him. If the issue starts to take over the majority of his time I would suggest encouraging him to get help. If all else fails he will have to find a place of his own again...what is being done to encourage him in this direction?

Maybe the whole thing is being exacerbated by the way in which his life has changed. If he feels he is making progress towards independence again the situation may well improve.

Stay strong and support him and your family the best you can...i'm sure he doesn't mean any harm by his actions he may just be having his own difficulties and doesn't quite know what to do about them.

I wish you luck.