I'm not in your situation exactly as I don't have 2 girls who fight day in and day out. I have 2 preschoolers, a boy and a girl, close in age who get along pretty well, but often enough they get into squabbles that last too long, or are over ridculous reasons, etc. To teach them about reaching out to others we help with outreach programs at our church and the local chidren's hospital doing nice things for others. It ocurred to me that promoting that at home would be a good idea. I'm thinking about maybe having them do things like straighten each others rooms occassionally, saying something positive about the other every day, etc. I read them a book a while ago called "Have you filled your bucket today?". It teaches about making people feel good (filling their emotional bucket) vs. making them feel bad (emptying their emotional bucket). It made an impact with them. I believe there are versions for younger kids and for older kids. As far as the toothbrush incident goes, I probably would have sent the singing sister for a timeout and if your kids get an allowance, maybe have the licker buy a new toothbrush for her sister. Not knowing how old your girls are it is hard for me to say for sure. Best wishes to you.