Q. At 5 years old, my child is still wetting the bed. Shouldn't he have outgrown that by now?
A. Not necessarily. Children that age are still gaining control of their bladders; in fact, 15 percent of 5-year-olds wet the bed. It's also more common in boys and among kids whose mother or father was a bed-wetter.
I'm assuming that when you say "still," you mean your son has always wet the bed. If he was dry for a while and has just started doing it again, if he's having accidents more often than he usually does, or if he's wetting himself frequently during the day as well (an occasional slip-up is okay), take him to see his pediatrician. There may be a medical cause, like a urinary tract infection or, more rarely, a neurologic problem or diabetes. He should also see a doctor if he's having other symptoms -- like fevers, frequent stomachaches, snoring or other signs of disturbed sleep, or any numbness or weakness, especially in the legs -- or if he's still having accidents after he turns 6.
Keep in mind, too, that sometimes children will start wetting the bed when they're nervous about something or have recently gone through a major life change (a new sibling, a move, or a death in the family, for example). If your child seems anxious, sad, or moodier than usual, his pediatrician, who should know his background and history well, can recommend sound ways to reassure him.
Most likely, you just need to wait out your son's bed-wetting. While you do, put a plastic cover on his mattress, and try to make sure that he doesn't drink too much after dinner and that he's eating plenty of fiber -- constipation can make bed-wetting worse (in some cases, it can even cause it). And please don't punish him or make him feel bad for wetting the bed. I bet he'd stop if he could.