It's mostly how they treat each other when we've been out and what I've heard from my girlfriend. I think it's mostly the "I don't care" attitude they seem to have about each other. They just often refuse to do the smallest favors or show any kindness whatsoever for basically any reason. I was raised the exact opposite and it makes me so frustrated to see family act that to one another, but I know I can't say anything about it. It's not my place.