What Could Blisters On Legs And Thighs Be Indicative Of?

My daughter watches a 2 year old little girl, and she was dropped off dirty so my daghter gave her a bath, and noticed she had bad blisters on her leg going up her iner thigh, and called me and said that her privite area looks different from when she hs changed her before, she asked me if its suposed to be stretched all out and bigger,, i told her to researh it online, and call the child abuse number,