Hi L.,
I too am a stay at home mom of 2 boys. My oldest will be 6 in april & my youngest will be 4 in august. So I'm right there with you!
My son (who is going on 6 next month) had a very hard time potty training overnight. My pedi said it's normal too. For starters, don't make it a 'big issue", be very calm & never yell or be upset (even if it's at 2am). Have him help you with the clean up part & figure out (with him) a new bedtime routine.
We first started with the 'no drinks after dinner'. which made HUGE difference. Even when he begged & cried for a sip of water, we HAD to refuse him. And just doing that alone narrowed the bed wetting from every night to 3x a week. Also, he had to go potty every 1/2 hour from finishing dinner until bed time & then once more right before he climbed into bed. So if you eat around 530 & finish around 6 - have him go pee right away, then again at 630, 7, 730 & then 8pm (our kids generally go to bed between 730 & 8). If he doesn't go each time, it's ok - the point is to try to get it all out before he falls asleep. Then if I'd read them a few stories, when I finished & if he wasn't asleep, I"d make him go try one more time to pee.
Now he gets up with no problem in the middle of the night to go potty. I think we've had less than 5 accidents at night in the last 7 or 8 months. So obviously something we're doing is working for us.
I do recommend a pull up at night until he can get the hang of getting himself up at night. I actually set my alarm for 30 minutes before his usual 'accident time'. I found that usually around 2am (for my son - everyone's different) he'd wake up with a wet bed. So I'd set the alarm from anywhere between 1 & 130 and actually go & wake him up & take him in the bathroom & have him go pee. And he usually went! And then he'd wake up in the morning w/dry pull ups. After 3-4 weeks of getting into that routine & getting used to it & him having a dry pull up just about every night for those weeks, we switched back to underwear at night. He got up on his own to go to the bathroom (i still got up with him - i'm not a very heavy sleeper) & no more accidents.
It's a process & it's harder on your kid than it is for you. It's a huge self esteem buster. Anyways, I hope these tips bring some help to you. Just let him no he's not the only one & it'll get easier. But just to let you know now, if noone's told you yet, it can last MUCH longer than 7yrs old. My youngest brother had accidents until he was almost 15 yrs old. My mom was so patient & kind to him that thankfully he didn't get too upset about it, but I know for a fact it was hard on him for sleepovers & things. He missed out on alot due to the problem.
My 3 yr old was much easier - he's not even 4 yet & doesn't have any accidents at night and he too gets up at night to go pee. His accidents are once in a blue moon. so it just goes to show that all kids are different.
So if you're up to it, give it a try. Cut off his drinks after dinner & make him go pee often ... and if you think it'll work, try waking him up at night to go as well. It was a life saver in our house. Good luck & God bless!