Sibling rivalry: My children are constantly squabbling and name-calling. If they're not fighting over who sits where in the car, they're cursing each other out over control of the remote.
Sibling revelry: Parents have to lay down ground rules about how family members should be treating one another. And they must communicate what their expectations are, clearly and often, says Faber. Otherwise, kids will behave as lawlessly as we let them.
Talk with your kids about what's going on and how you expect their behavior to change. "You can say that while you can't demand that they act like they love one another, you do require civility. There is such a thing as kindness without closeness. It's a lesson that will go a long way in the outside world," says Braverman.
Emphasize that abuse of any kind won't be tolerated. Pinpoint key conflicts and ask the kids to suggest guidelines -- and the consequences for not following them. For example, you all might agree that commandeering the TV clicker from a sibling automatically loses the bully an hour of viewing time. The next time it happens -- and it will -- your job is to remind them of the agreed-upon punishment.