Three failures, not one. The night hormone that tells the kidneys to slow urine (vasopressin) doesn't rise enough, so the bladder overfills ¹. The bladder itself may be small or jumpy at night. And the child sleeps too deeply to wake to a full bladder: in a lab, enuretic kids need a louder noise to rouse than other children ². It runs in families: one parent's history puts a child's odds 5 to 7 times baseline ³.

Two tools do the work. The bedwetting alarm is the cure: a sensor sounds the instant it gets wet, and after 6 to 10 weeks the brain learns to wake first. It's the only option with lasting dryness after you stop, with half of treated kids reaching 14 dry nights in a row ⁴. Desmopressin, a tablet replacing the missing hormone, works from the first night in roughly 1 in 3 kids and stops the night you stop it ⁵. Alarm to be done with it; desmopressin to cover a night away.

The order it improves in. The alarm fires later in the night, then less often, then a dry morning, then a streak. Somewhere in the two-to-four-month window the alarm comes off; about half who finish stay dry, and most who relapse hold on a second course ⁴. The first sleepover in two years gets a yes. Self-esteem scores that sat below average while the wetting lasted climb back to normal once it stops ⁸.