How Scared Should We Be?

Yesterday, Safa made Eden cry. Eden. The same Eden who at about 16 months pushed Ava and knocked her flat on her ass. Safa turned 11 months old yesterday. She is the only baby I've ever known who retaliates. If her sisters take a toy from her she gets mad. Really mad. She screams and tries to scratch them. All other babies I've known might cry, but most just look a little bewildered and move on to something else. Safa has a bit of that third baby scrappiness you sometimes hear about. I don't think we need to worry about her holding her own as they get older. But the other two might need to sleep with one eye open.