My experience with my foster son

He was also a very heavy sleeper. I would set a loud alarm for 4am for him to get up and pee and he would sleep right through it till I got him up to pee. And he would still wake up wet. We tried limiting liquids, doing the prescription medicine...nothing worked. Finally it occured to me that he needed to pee a lot during the day and what if his bladder was on the small side? I got him to start holding his urine for a little while during the day before going to pee (but tried to encourage him not to go overboard) and wham no more night accidents. He was 9 at this point. If nothing else works and you are still in this position down the road, it's an idea to keep in your back pocket. Hopefully he just needs to mature and produce more vasopressin and this issue will address itself naturally. This did not work for my foster son though as even the px stuff did not help at all.