Just frustrated

So my brother (13) is on the spectrum of autism. It's mild, but he can function almost perfectly. But he's spoiled as fuck, literally. My parents baby him, accommodate to his wants, give him everything he wants, and do everything he wants.

It's been this way for a long time unfortunately, they give him half my shit too. Markers I got for my birthday, there given to him. A new book I bought with my own money, it's his immediately. Any food/snack or drink I buy for either myself or for a friend, it'll be his. All of this to avoid a meltdown or him getting verbally mean, slamming doors or punching someone.

My brother has a history of punching me, our younger sister (10) whenever we say something he doesn't like. Say ballet is a sport, or physical activity. He gets pissy and says 'no! Football is a sport, ballet isn't.' and if you try to tell him otherwise, he gets really upset and starts hitting shit or us.

Our parents won't do shit about it, they excuse his actions and say 'He can't comprehend his feelings as well as we do' and 'He probably doesn't understand it's wrong/his strength.'

Especially my mom, she will excuse his behavior and anytime I bring it up, she gets annoyed with me and tells me off.

My brother also makes cruel jokes about harming animals, people with disabilities, people that are LGBTQ, etc. We own three dogs, a cat and two bearded dragons. He has made many jokes about them 'getting' hurt and I hate it. I own both a cat and a dog, and yet I can never sleep with my dog nor cat because my brother always wants to sleep with them or have them in his room.

There are many things I could talk about or say in this vent or rant about my brother, but not all of it would probably fit here.. I'm just frustrated at this point, tired of exhausted or whatever. I have a few mental struggles of my own, but I rarely get any help with them because my parents either don't wanna talk to me about it, claim my brother needs more attention then I do or the good ol' 'Your a girl, your going through teenage hood!! These feelings will pass!' type of shit.

This vent kinda feels all over the place to me, but that's how things feel right now with my home life.