M.G.
My son is 5 and he wears the good nights pull ups every night...and sometimes leaks through those! He's been potty trained for a long time too. My father-in-law is a kidney doctor and he says that it is not unusual for boys to need nighttime protection through the age of 8 or so. I know they can get expensive, but you and he will be much happier if you aren't waking him up at night (uninterrupted sleep is good for his growth and development) and if he wakes up with dry sheets. Another thing my fil said is that this type of thing is familial. He wasn't dry at night until he was older and neither was my husband. Give the kid a break!
M.