None of the sibling pairs have really been introduced yet in my current comic, but they're all... bad or distant. One is extremely sexist and talks down to their sibling a lot, the other is so jealous of his sibling. He SA's his sister's girlfriend to spite said sister and hurt her via her lover. The best sibling relationship is distant and they don't really talk, but it's clear they still care a bit. Not enough to stay in eachother's lives at the end, though.
In my robot comic the sibling dynamic is toxic as well. To the point that the brother removes the sisters legs and keeps her as a prisoner, after killing her lover of course. Dude torments her until she attempts suicide, then his actions get them both killed.
Even the novel I haven't worked on for months about 4 siblings is just... miserable. The eldest beat them, the eldest sister ran away and doesn't speak to any of them, the two younger ones run away together and I guess they're fine... but the youngest sibling is just an emotional punching bag and isn't bothered with unless the older of the two is single (not in any sort of inappropriate way, he'd just rather spend time with lovers than family.)
So I guess I write siblings according to that pesky evil stereotype. But I fully admit that would probably stem from my less than great experience with my sibling. He's younger, the favorite, and he could get away with anything. Including beating me when the teen years were reached without so much as scolding, and should I "tattle" or fight back I'd just incure my mother's wrath too; for the "mature" thing was to shut up and take it, according to her. He threw himself down the stairs, blamed my friend in attempt to isolate me, which would have worked if we didnt have an adult visiting that called him out for lying when mom began screaming at me. He held my cat against the wall by the neck... and now he's homeless, addicted, and only comes by when he wants money or for me to hide stolen goods (I never help him).
It's just hard to write a good sibling dynamic when my own most prominate memory of my sibling is holding my bedroom door closed with all my strength, feeling it buckle and bend each time he tackled it from the other side. Screaming at me for... something. I don't recall what he said, probably something about hurting him when I peeled his fingers off my cat's throat. I hadn't reacted or done anything to his abuse in months at that point so it must have been shocking to have me finally fight back again. Tears running down my face as I stare on at my poor cat coughing and trying to catch his breath by my feet, knowing I had to keep that door closed not for me-- I didn't care about me anymore-- but for him.
Write what ya know, baby. But hey, at least the "distant and not in their sibling's life much, if at all" wasn't a trope on your list so I've only sinned with my abundance of evil ones.
