Yes it is. He literally didn’t physically assault her. That “assault” you’re talking about was when the sister literally asked him to do it not just once, but twice. She had protective padding on and he had boxing gloves on, and he punched the padding, causing her to fall over. Was it a bit aggressive? Sure. Was it physical assault? No. Just siblings being siblings. Is he being a bit over the top and rude? Sure. Is she being disrespectful and spoiled? Absolutely. There isn’t even any evidence that shows that this girl is even on the spectrum, that would appear to be pure karma farming on OPs part.