reappearing contagious itchy blisters

[katalana]

6 weeks ago my daughter developed some itching blisters, which would appear in the evenings, stay on at night and then disappear untill the next evening. Sometimes they are watery blisters, sometimes just red kind of [COLOR=blue ! important][COLOR=blue ! important]rash[/color][/color], terribly itching. She slept in my bed a few times when I wasnt home. First we thought, as the [COLOR=blue ! important][COLOR=blue ! important]doctors[/color][/color] are pretty clueless, that it might have some psychological reason. BUT then after 2 weeks I also developed it and another 3 weeks later my husband joined us. All of us are affected in the evenings and night, but not only when sleeping in this bed. (Myself I had even been to [COLOR=blue ! important][COLOR=blue ! important]hospital[/color][/color] for a few days for some other condition and there it was itching too) We went to different doctors, each of us. They diagnosed different things, some just gave Cortison cream, some said its fungus, some said its scabies (which i would exclude as there are no visible tracks which one should see on the skin if its caused by these animals and it starts appearing in evening time, where ever i/we are.) and some simply say "we don´t know"
Any idea???