It's a problem many children and their parents have to deal with: bedwetting.
Researchers are learning more about who's most likely to suffer from it. A survey suggests children whose parents wet the bed are far more likely to be bedwetters themselves.
Mum of two Tracey Thompson used to start every day making up her son's bed with fresh, dry sheets.
"No kid actually wants to wet through the night, they're either wetting because their bladders aren't developed enough to last all night or they're sleeping too heavily to actually wake up," she told Newshub.
In a lot of cases, it's genetic. Research has found if one parent wet the bed, there's a 44 percent chance their child will do the same. If both parents did, there's a 77 percent chance.
It's also common - around 100,000 Kiwi kids wet the bed and it can cause other problems when it comes to sleepovers and school camps.
"This big issue is the kid's apprehension to join in what everybody else is doing," says Ms Thompson.
But she has a secret weapon.
"We use Spiderman nappies every night. Which means they go to bed, they wake up in the morning, there's no big issues, no accidents, life goes on as normal."
According to Anita Quensell, clinical director of Plunket, that's precisely the way to tackle the issue.
"If a child is having this issue and it hasn't been discussed that it's okay and it's normal, they will be feeling stressed, they'll be feeling anxious, they'll be worried about going to bed at night," she said.
She says eventually most kids do grow out of it, it's just a matter of time and patience.