My daughter (aged 5) has what looks like a burn on her chest. It is about 3 inches by maybe 2 inches. It started as what she called "sunburn", and over the course of the day has developed blisters. Now a second spot is starting on her arm just above her wrist, and possibly on her upper arm. Any ideas?

Optional Information:
Female , Age: 5

Already Tried:
Asked here once, and got no answer