my daughter who just turned 2 years old has started to have these welt like blisters on her bottom. I took her to the doctors this morning, he didn't know what it was. She has no fever and nothing changed in her diet. Also he said if it spread to call him and so when she woke up from her nap a few hours later, i noticed some on her leggs now. So I called back to the Docs and they said they still had no idea and if she developed a fever to take her to the E.R. They don't seem to bother her much but she is 2 and not going to tell me if they itch or not but I haven't noticed her itching them either. I have heard maybe a bite from some bug but they do not look like bites at any level, they are large welts that kind of look like a blister. What should I do. It started on her bottom and is now spreading downward to her leggs