1. they never leave you alone
2. they take all your shit
3. they're always favored bc they're the "baby"
4. they never f**king shut up
5. you get punished for things they do bc it always affects both of you
6. no sense of personal space
7. no sense of privacy
8. unnecessary picking at you (ex: my brother choking me out)
they cannot be reasoned with
also: you're with them so much that you are going to fight with them guaranteed, even if you're nice to them, they will attempt to beat the shit out of you