Siblings are fighting?

Alright well me and my sibling do fight. We are like total opposites and we have to share a room. But I'm the youngest and she's the oldest. I cry, she kicks me while I'm sleeping (literally). It's not awesome because she's 21 and I'm 13. She"s a bit of a neat freak and I only clean when my parents ask. I think my parents are doing the best they can with them fighting as much as we do. I don't think they've failed because I'm still a good kid. I would teach my kids not to fight though. Possibly better than my parents. I think she just isn't going to get along with me and I've faced that. At least I learned never to be her roommate.