A new study suggests better sleep habits could help prevent childhood obesity.
Researchers at the University of Otago were surprised to find that sleep lessons cut obesity rates in half, even if they didn't improve sleep.
Getting a baby to sleep can be a total nightmare and Cherene Daley became a baby sleep consultant after having difficulties with her first child.
With her second, six-month-old Haven, it's a breeze.
"I pick her up and say, 'Okay, we're going to go to bed now', take her into her room, pop her in her sleeping bag," Ms Daley told Newshub.
"We turn on the white noise and we close the curtains, and then I'll kiss her goodnight, say a little saying like, 'Mummy loves you, it's sleepy time, I'll see you soon', then walk out."
She says good rest is important for growing babies.
"It links into development and their temperaments and how they can cope with things, even at a young age, so their frustration is a lot lower when they're learning to do things like crawling and rolling and walking."
Now researchers say it could impact on weight too.
The Prevention of Obesity in Infancy study involved 802 Dunedin families. Some were given an innovative sleep programme, which included a sleep class before the baby was born and a visit from a sleep nurse at three weeks.
Professor Rachael Taylor says one of the main focuses was on self-regulation.
"A lot of the advice and guidance was about giving your baby, when they first go to sleep, or if they've woken up in the night, giving them a chance to settle themselves back to sleep."
The bizarre thing about the study is it didn't even help babies to sleep longer - but when they reached the age of two, their obesity rates were halved, from 12 percent to six.
What they don't know is why.
"We think it could be something as simple as if you sleep less, you're more tired and you don't want to be physically active," says Prof Taylor.
"You've got more time to go to the fridge, but there are some hormonal things associated. If you don't get enough sleep your appetite hormones are all out of whack."
Ms Daley has her own theory.
"If children have that ability to self-settle as oppose to perhaps being constantly fed to sleep when they're not necessarily hungry, that will allow them to eat and regulate themselves their hunger as oppose to always being given little snacks here and there and never being able to develop that true hunger themselves."
Whatever the reason, scientists say it works to cut obesity rates, and Ms Daley says it works for sleep too.