Time to stop being soft and gentle and book her into a kick boxing class. They are about for juniors, my friend's daughter joined one. My niece accompanied her daughter to school, entered the class room and sat at one of the desks and when asked to leave said she was staying there until she could be sure her daughter was not bullied any more and that she would persist every day it went on. They soon got off their backsides and stopped it. Don't know if either of these would work though. You have to be tough in this world.