I used to use two accounts now and then, 1 main and 1 for friends and my brother.
A good while ago I got a new Xbox and had to transfer all the stuff from one to the other, including the GTs.
My main account had been remembered but the secondary one hadn't, and basically no one can remember what the Live ID associated wit hit was, we all know the GT since that came over but the log in details never.

Does anyone know how to find out the parent/child Live IDs attached to accounts?
I had tried Xbox support pages but they're not exactly helpful in this, nor is phoning them since they don't answer.