Just stop!
His brain has not turned the chemical to stop the kidneys from producing urine when he goes to sleep. He has absolutely no control over this. NONE!
So stop, there is nothing you can do until his body turns this on. He could go to a Pediatric Urologist but they will say he's not getting enough fluids and you're making him constipated by limiting them. So the weight of the pooh pushes the urine out when he falls asleep, when his core muscles relax the most. Then he'll put your son on massive doses of laxative to see if that's what it is and if it's not what is causing the wetting he'll give him a med that is supposed to help. It might work and it might not.
My 14 year old grandson still wets the bed every night. He may have been molested as a child when he lived with his dad. Dad had people living there all the time and my grandson was exposed to a lot of stuff until the state took him away. The Urologist says there is nothing to gain by giving him meds. The side effects are so much that the doc feels it would hurt him more to give him the pills or squirts of stuff than for him to just wet the bed each night. So he takes no meds.
My 9 year old granddaughter woke up Friday morning for the first time in her life dry. She has been dry every morning since, am I going to let her go without a pull up? No, she's going to wear one every night until she's been dry at least a month in a row!
She took a pull up to every sleep over, every time she went to a her mom's, everywhere. She never went without one because it is worse to wake up wet in front of her friends or others instead of discretely going to the bathroom and putting her pull-up in the bottom of the trash can.
I never fought with her about it, I never woke her up during the night, I never told her she should be dry, nothing. I made her mom's life a living hell when she was little over wetting the bed. I hated waking up to the soaked sheets every morning. I didn't know about protective mattress covers and we didn't have pull-ups back then, just training pants. I threw away more mattresses back then and simply hated the whole urine thing. So I woke her up every hour and made her life hell over it.
I know more now. I have a pediatric urologist who told me about it and that it wasn't the kids fault and how their body is made to work. I am different now and know more.
Your son is doing what we all do when we're awake. He gets woken up and he automatically starts holding the urine, those muscles just tighten up and hold it. He doesn't wake up enough to actually process the activity so he doesn't go, even if he does he is still producing urine as soon as he goes back to sleep so he'll be wet anyway. There is no reason to wake them up. This makes him sleepy and tired all the time and it makes you tired and grumpy too. Resentment comes and then no one is happy in the home. So sleep all night, put a pull up on him, put protective pads on the sheets, make life easy, don't add money and waste your time washing sheets and other bedding every day, put this child in a pull up and tell him he'll grow out of it one day on his own.
Do you wake up several times during the night to go? If so I suggest you get tested for Diabetes because normally an adult does not wake up during the night to go pee, they stop making urine during the night and as soon as they wake up their kidneys kick in and they feel their bladder fill. Waking during the night to go pee is one of the questions they ask you to help determine if you need to do testing for Diabetes. If you are waking up occasionally then it could be that you had a sleep cycle that was very light and your kidney produced urine then you woke up.
Your son is normal. Lots of kids his age still wear a pull-up every night. He needs to know there is nothing wrong with him and they one day he'll wake up dry.
Give him more to drink, it truly will help. Do some research if you like. My hubby swears that if the kids don't drink chocolate milk right before bed they should be dry. That has NOT proven to make any difference in the kids. They are still wet each morning no matter what.