With 3 other siblings, even if Mom knew someone was going through her stuff it would be impossible to determine who it was.
My Mom passed 5 years ago. One of my brothers lived with her his whole life, and passed 2 1/2 years ago. Myself and my other two siblings started cleaning out the apartment, and then COVID hit. For a few months we left the apartment as it was. It was in a huge building (like three towers of 150 apartments each with a connected lobby) in New York, a real hot zone at the beginning of the pandemic. Not wanting to hold the apartment until COVID died down, we started going in individually. The last two times I was there, I was fully dressed, and took a couple of items from my Mom that I knew would otherwise have ended up in the trash. So you can say I’m still wearing her stuff.