Well I could've written a small novella on this... back when my girls were at a gym where they practiced 6 days a week and they were fairly new there, one of the older girls who had been there her whole gym career decided to make it her life's work to torment my youngest on a daily basis...which of course I was not aware of for a while. When I became aware of it, I spoke to the coach who in his own warped way said "oh we all talk to each other like that" to which I replied "well then it stops today, because I'm not paying for my 10 yo to be bullied" . He said he would speak to the bully and predictably, it got worse so I told the coach , either you stop her or I will confront this kid (who was a 17 yo prima donna) . Two days later, my daughter comes out in tears, AGAIN, because of this kid so I March right back into the gym and end up face to face with Bully, and I tear her a new one ...not my finest moment but nothing untrue was said ... she says "I'm going to tell my parents what you said " ... I say "I dare you and have them call me for the full account of your behavior"
Well doesn't the dad (who's kinda a gruff rough around the edges guy who I didn't know at all) call me AT WORK the next day to "talk about what you said to my daughter" . I was taken aback at first but I ended up having a 30 minute conversation with him about exactly what his daughter had said and done to my youngest in the months prior and at the end of the call he said to me, "sadly, this sounds exactly like how my daughter could behave and I will put an end to this and it will not happen again... but if it does, please call me directly and try not to get into with her " ... I agreed and he obviously spoke to her because she returned to the gym, tail between her legs, apologized to my youngest with a "I didn't realize it was upsetting you " but whatever... it stopped and they actually were pretty friendly after that .
Ironically, the coach didn't put a stop to it and I was actually shocked when the dad responded as he did but I would've left that gym if it hadn't stopped because as Txgymfan says, it's not worth putting up with to be bullied on a daily basis.