My sister’s dog keeps trying to eat my kittens

My sister (28F) has a dog with the highest prey drive I’ve ever seen in a dog and she usually doesn’t live with me and my parents but she will come down on holidays and such and bring her prey wanting dog. And that dog drives me insane. She barks non-stop and growls and bites if you get too close to her treat/food and is just insufferable all around. Don’t get me around I don’t think she should be put down or anything but I do want my sister to not just leave her dog at home all day. This dog will stalk by my door and look for opportunities to run into my room to get the kittens. And I know for a fact she wants to eat the kittens because we first let her see the kittens while they were in a cage just as a small introduction and she immediately went into predator stalking position and that’s when I KNEW this dog was hungry for baby kittens (these kittens are also small for their age (1 month) so they look like easy game).

Anyways I keep asking my sister to try her best to keep the dog away from my door because one time she managed to run in (she’s a small dog with small dog syndrome) and chased one of the kittens while barking extremely loud all the way down the hall. The kitten barely escaped with its life because it hid beneath the couch which the dog was too big to go under. My sister refuses to discipline her dog or even keep her in a roomy cage/room while my sister goes out. She claims that dogs weren’t meant to be locked up and I know that but my kittens lives are actively at danger and she doesn’t seem to give a single shit 😃anyways thanks for listening to me rant and let me know how I can reemphasize the safety of my kittens in a way to get my sister to finally listen 😍😝