Bedwetting Support Group
Bedwetting (or nocturnal enuresis or sleepwetting) is involuntary urination while asleep. It is the normal state of affairs in infancy, but can be a source of embarrassment when it persists into school age or the teen or adult years. Find others who are coping with a bedwetting problem and share your experiences and questions.

I agree, go see the doc, and get checked for simple causes (uti, etc.). Also, maybe a sleep study is in order, given the dreams being originally associated.
If they don't get a simple answer, you probably won't get one at all.