How do you stop blisters from sun burn hurting?

My daughter has just come back from her hols with her grandparents. They stayed in the u.k. She had suncream on but wasn’t toppped up. She has severe blisters on her shoulders and her back is very red. A & E told me to put a non perfumed cream on her back and calomine lotion on her blisters, but she won’t let me any where near her blisters! I also have various aftersun creams that contain camphor and aloe vera. What else can I do for her?