Am I the ss@ hole if I don't want my little sister to keep my stuffed penguins?

This is a community like r/AmITheAsshole, except unlike that subreddit, you can post interpersonal conflicts. Anything that's AITA, including relationships, hypotheticals, and would I be the asshole (wibta) posts are allowed. AI scenarios/posts are not welcome or tolerated. An elaboration on our rules can be found here: https://www.reddit.com/r/AITAH/wiki/index