Urine issues can certainly be caused by GD! I was on a roller coaster of hyper/hypo for a few months and came to know that urinary incontinence was the first sign that confirmed I was becoming hyper. I also had repeated bouts of cystitis and irritated bladder where I needed to go all the time, but only a trickle would come out, just like your daughter. I had 3 urine tests over a couple of months and they were all negative for infection. It was all very unpleasant and distressing. However, endo didn’t seem to think it was related to GD. I was referred to a urologist and he hadn’t heard of a connection either. I am now in remission and the urine problems have gone as well. There is so much that is unknown about this disease.
best of luck to you and your little girl!