I'm sorry your dealing with this. Even though the prognosis is positive, I can't imagine how disconcerting this is for you. We live to keep our kids safe and wish we could take away all their illness and pain. If her hair has started to thin or fall out, it may be best to go ahead and shave it. Bald is beautiful and she is no less of a woman without it. Have the whole family and her friends shave too, in solidarity. It would make her less self-conscious.