I just wanted to say that I have the same concerns about my daughter and, like you, have been unsure what to do or say. She's also 13 and her body has changed a lot since going through puberty and just growing older. She's about 5'3-5'4, 130lbs and training level 10. Honestly, I definitely believe it has affected her skills and progress a little and I think it is making things harder for her. But I would never say anything to her about it or want her to feel bad about herself. I know she's already self-conscious about her body (she will not practice without shorts for example). I do think she could be making better food choices too and that is something I am working on with her. She eats a normal lunch and a small snack and then doesn't get home from practice until 9. But from 9 to bedtime she is so hungry from the day and she just eats a lot. Anyway, I just wanted to let you know that I get it and that you aren't alone in your concerns.