What do I do here?

Back in March my sister accused my mom of hitting her and pouring water on her. And my mom poured water on her. She was drinking, yes but she never hit her.

Anyways, my sister has a protective order on my mom and has since came back in the house (mom's house). They can't be around each other and my sister is making messes, has the garage filled up with her shit.

My brother is on speaking terms with her and nobody said she could stay here.

But it's been a few weeks I told my mom to call the police.

It's so stressful, my sister is acting super shitty. She's 45.

I don't talk to her nor will i ever. But she isn't leaving.

Last resort is to call the police. I told my mom to call them cause I feel like they would be less likely to arrest her cause she is following the no contact order.
What do I do here?
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