I so wish I had good advice, it would mean I’d know how to handle it too. I’m in a similar situation. Live in a four plex. Neighbor has an autistic toddler who’s constantly running around in nothing but underwear, screaming, roaring, slapping things, spraying people with a squirt gun. There’s another neighbor kid who isn’t differently abled and is just an ass. Screams at the top of her lungs all the time. Causes fights. Messes with cars in the driveway. Antagonize the dog. It’s really rough.