When this aunt is concerned, she asks Reddit:
My husband (33M) has a sister I'll call Jane (36F) and she has three kids, the youngest one is Jill (8F). Jane and her kids visit often so my husband keeps toys around for them.
A short while ago my husband got me some Meemeows. My cat Chewie decided that she really, really liked one of them and the fuzzy brat commandeered it as her pillow. If you move it from her usual spot on the couch where I like to sit for work, she carries it back.
Jane was visiting with Jill. My husband and I were both home and I was sitting on the couch doing some work. Chewie was next to me on the couch with her Meemeow pillow snoozing away.
Jill came up and asked if I would move Chewie so she could get the plush. I told her no and explained that the plush was Chewie's and it would be mean to take it from her, especially while she was napping.
I told her there were some new toys in the box my husband keeps around and look in there for something. I got up to get a drink and some papers from my bag and Jill walked by me hiding the plush behind her. I took it from her and reminded her I said no and she needed to listen and leave Chewie alone. I put it back next to Chewie and went back to work.
Couple of minutes later Jane came into the living room demanding to know why I took a toy away from Jill because 'It's a cat, not a human, and toys aren't pillows. don't parent my kid.'
I thanked her for revealing my cat was not actually a human despite her acting otherwise and I was forever grateful for her pointing out the difference but the fact remained, I told Jill no and to leave the cat's things alone and she didn't listen.
Somehow that has snowballed into Jane and my husband's brother suggesting that another family member host dinner next week so the 'human kids won't take backseat to an animal.' My husband is on my side but I'm kind of questioning if I should had just let Jill have the dang plushie for an afternoon or not. AITA here?
TA Jane (edited because I got the names mixed up) is teaching her daughter that even when told no she can have what she wants. In other words a spoiled brat. If she can’t respect your rules then she shouldn’t be allowed over because this will only get worse.
NTA. But I would definitely agree that someone else gets to host family dinner to give yourself a break from the entitled SIL. An 8yo should be able to follow a basic, “that’s not yours, please leave it alone” at someone else’s house.
And if they need a reminder, their parent should be the one to step in and reinforce it instead of whining even louder.
NTA. When my kids visited my brother and his wife, who LOVE their cats like kids, the kids always respect the cats' areas and their stuff. They respect OUR cats' stuff too. Surprisingly, it's possible to raise kids who have empathy.
OP, you're 100% in the right, but maybe these kids shouldn't be stopping by until they learn some manners. I would start telling the sister no when she wants to come over until they make some changes.