Touch wood, my mum's been fine. She has blood tests every three months, and has been on Arimidex, which is apparently a good drug to be on, and she's been quite upbeat within herself.
When mum was diagnosed, I found the Breast Cancer Care website really, really helpful. You can ask for advice, join in chat rooms, and everyone is so friendly. I was very down at the time, but chatting to people who'd experienced the same thing was really helpful for me.
As you already probably know, you're also advised against using any soap/bath foam/shower gel etc on the area that's being treated with radiotherapy. Your daughter may find that she gets a 'sunburn' type of rash on the area that's being treated, and mum found that pure aloe vera gel (100% if you can get it) worked brillantly. Drinking lots of water helps too.
Do let me know if there's anything I can help with, because I know from experience what a difficult time this can be. Take care, and lots of love and best wishes to you and your daughter xx