DC who are 9 and 11 fight all the time - they literally cannot be left alone for 5 minutes without WW3 breaking out. It's both verbal and physical, and location makes no difference. I've just returned from a trip to Tesco, where they fought in the car park as well as in the store. The fighting continued throughout dinner and escalated upstairs where she turned off the light when he was in the loo.
They've never got on, but DH and I are really at our wits end. Not only is it exhausting listening to it and dealing with it, but it spoils everything we try to do as a family and DC3 who is 21 months is starting to copy them. The thing is, when they are apart they are great kids - polite, well mannered, lovely children, but simply hideous together.
What do you do in this situation? Do you punish both of them, regardless of who starts it? Do you ignore? Please help!