Wow, thanks so much for all of the advice and encouraging words! We've been taking a lot of your advice, and they're still arguing, but much less. Emma has realized that when she bursts out in anger or frustration at something that Kenna does, Kenna retaliates and will not back down. So, if Emma begins with a calm voice, Ken is easier to work things out with. If I just remind Emma at the beginning to use nice words, it usually doesn't escalate as fast. So, thanks again everyone!