My daughter wrote a letter at school today. She should not have delivered it but did. Need help on deciding how to proceed.

My daughter is in first grade and has an intense distaste for one of the boys in her class. She has every right to dislike this child. Not only does he disrupt the class every day, making it more difficult for my daughter to learn, he can be a bully and ferociously physically violent.My daughter was on the receiving end of one of these outbursts a couple of months ago when he was at a play date at the neighbour's house. He kicked her in the chest and stomach while she was curled up on the floor no less than 5 times. She had fallen to the floor voluntarily in a wink murder style game, clipping his face with her hand as she dramatically "died". There was no pause between the accident and the outburst for my daughter to even attempt to apologise. I witnessed the whole event. I have worked with children for 12 years, including at risk adolescents and this would be very high on my list of shocking/ upsetting/ violent behaviours.His parents' response was "He almost lost that eye in an accident, he must have been really scared." He did give a standard apology, like one would expect if they both accidentally hurt each other, however.She was really upset and shaken by this, and he's now also on her soccer team. She gets one day break a week from him.However, she also asked for a whole class party this year. She's extremely excited for all her friends to come and has been planning since January. She explicitly asked not to invite this child, and only this child. I said to her that she can't do that, she either has to have just her close friends at the party, or all in.She opted for all in.He has RSVP'd in the positive and my daughter's response was to use her free writing time today to write him a letter asking him to keep his hands off the guests, basically. The substitute teacher allowed her to deliver this to him.I don't know how to respond to this. I mean, she has a right to be nervous of him, and to stand up for herself and her friends, but I feel like a school "okayed" letter (sort of) of the nature she describes is not the right thing to do, and toes the line of bullying itself.I really wish I'd just been more forceful about close friends only, but she was so excited.I basically feel like I fucked up, and the fallout might be very uncomfortable.My instinct is to "damage control". Contact the teacher and let her know what happened and possibly reach out to the mother.My other instinct is ignore it and to tell they parents if they confront me that he was very violent with my daughter and her feeling the need to write the letter is a consequence he should suffer.To my knowledge he does not have a diagnosis of any sort. via /r/Parenting http://ift.tt/2obRulh