Since the dermatologist does not know what it is I don't know if what I am thinking could be it or not. I have terrible allergic reactions to a lot of medications and that is similar to the symptoms that I have had. My rash gets everywhere including the palms of my hands and the bottoms of my feet. It resembles measles or in the face and chest it looks like a bad acne break out. Has your daughter been taking any new medications or vitamins or anything out that she did not use before? It could even be from soaps or detergents. Try to see if there is something that you can remember her changing and see if removing that helps.