I think it is perfect. I only have 1 suggestions. It might go over better if make a compliment sandwich so you don't upset your parents (unless she is the type of person that needs that type of message). I try and use my soft skills/customer service background since I can be too direct at times. After stating that she is in violation of your policies I would add that you would hate for DCG to miss out on group activities. Keep all of what you have and at the end add something like, Thank you for your support or thanks in advance for your cooperation or my favorite Thank you for trusting me with your most precious possession
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