Mystery Solved

My friend Ben put forth the best theory yet on the mystery allergy. The big question that made the mystery so mysterious was why the allergy started at our old house and continued at our new house. Her diet didn't include anything that could have caused the allergy, and we had eliminated the detergent idea, so there was nothing else that we could think of that carried over from the old house to the new house-- that is, except for the carpet cleaning chemicals.

We got our carpets cleaned before we moved, and the carpets were cleaned at our new house before we moved in. Whenever we were gone out of our new house for a good part of the day, the hives would go away. So the carpet cleaner chemical theory is very strong.