R.N.
She could have a bladder control issue. A urologist who specializes in children should be able to sort it out. I would explain to your child that if she doesn't start using the potty on command (peeing on command should be easy)with in 3 weeks that you will take her to a doctor to see if there is a problem.
My 3rd child had no nerves to his bladder and only peed when his bladder overflowed. We just thought he was being difficult until we brought him to the urologist. (it also unveiled other nerve problems) If the issue is not taken care of in a timely manor it cause kidney damage.
Don't be afraid to check it out. Holding for 12 hours and then soaking herself is not a normal bladder behavior. And the worst that could happen is that they will 1- find out what is really wrong and treat it or 2- send you home with no fears.