Many a parent has had a well-meaning friend or family member tell them to keep their baby awake during the day, so they’ll sleep at night.

But this is FALSE my friends.

You’ve likely heard the saying, sleep begets sleep. What this means is, children who nap well during the day, and at the right times, fall asleep more easily and sleep better at night. On the other hand, children who are overtired are more likely to have difficulty falling asleep and staying asleep at night.

Though this may seem counterintuitive, the reason is simple.

When babies miss their sleep windows, they begin producing cortisol, the stress hormone, instead of the calming melatonin that helps regulate sleep. You’ve heard of or perhaps experienced the “second wind” with your child. This is a result of the cortisol coursing through their little bodies.

Years ago, I worked with a family whose toddler would go wild around 7:30 p.m. and start running circles around the house. They thought it was adorable and that he just wanted to play. I said, well, yes, he is adorable, but NO, that’s not a sign of playtime, it’s a cortisol hit from missing his sleep windows. Simple solution. They put him to bed about 30 minutes earlier and he was sleeping soundly by 7:30 p.m.

If your child is having difficulties at bedtime, consider whether they need more sleep during the day. If you’re unsure or need guidance, contact a sleep coach who specializes in your child’s age.