Sleep regressions, age by age

This guide is general information only and isn't a substitute for medical advice. If you're concerned about your child's health, or they're unwell, please see a doctor.

Your baby was sleeping fine, and now they're not. Before you assume you broke something: you didn't. Most "regressions" are progressions: your child's brain levelling up, with sleep as collateral damage. Here's the usual timeline.

Around 4 months

The big one, though “four-month regression” is a term parents and consultants use rather than a published clinical milestone. Underneath it is ordinary baby sleep: Raising Children describes young babies sleeping in short cycles of around 50 to 60 minutes, and waking briefly between them is normal. If they need feeding or rocking to fall asleep, they'll often need the same thing at every overnight wake, which is what makes those wakes hard work. This is typically when families first look at how their baby falls asleep, and when structured settling approaches start to become age-appropriate.

Around 8–10 months

Crawling, pulling to stand, separation anxiety, and usually a nap transition (three naps down to two) all land at once. Expect bedtime protest and practice-crawling in the cot. Usually settles in two to six weeks once the new skills are boring.

Around 12 months

Walking and words. Some babies flirt with dropping to one nap here, but most aren't ready until 14–18 months, so hold the two-nap line for a few weeks before restructuring the day.

Around 18 months

Toddlerhood arrives: independence, big feelings, and a newfound ability to say no to sleep. Separation anxiety peaks again. Warm, boring consistency at bedtime is your friend; big routine changes mid-regression usually backfire.

Around 2 years

Later bedtimes as sleep needs drop, nightmares appear as imagination grows, and many toddlers test whether bedtime is negotiable (it isn't). Also watch for the too-early nap drop, since most children keep a day nap until around age three.

What helps, whatever the age

Hold your routine steady. Regressions are a terrible time to renovate bedtime. Offer extra comfort without building a new long-term habit you don't want (a week of rocking to sleep can outlast the regression that caused it). Watch wake windows, since overtiredness makes every regression louder. And lower the bar everywhere else: a fortnight of survival mode is allowed.

One note on newborns: rocky sleep from birth to three months isn't a regression. That's just how newborns sleep. Frequent waking is normal and protective at that age, and no structured sleep program is appropriate yet.

When is it more than a regression?

• It's lasted more than six weeks with no improvement
• Nobody in the house is functioning: safety, work, mental health

Both are exactly what sleep consultants are for.

A few things point to a doctor rather than a settling plan. Raising Children advises seeing your GP if your child snores most nights or over a long period, breathes through their mouth, or gasps, chokes or struggles for breath in their sleep, or is unusually tired or hard to wake during the day. Difficulty breathing, pale, blotchy or blue skin, or being very drowsy or hard to rouse are signs of serious illness that healthdirect says need urgent care. And if your child seems to be in pain, is feeding poorly, or isn't growing or gaining weight as expected, see your GP or child and family health nurse, because no settling method fixes a medical problem.

Sources

• Raising Children Network, About sleep and sleep cycles
• Raising Children Network, Baby sleep 2 to 12 months
• Raising Children Network, Toddler sleep
• Raising Children Network, Snoring in babies, kids and teenagers
• healthdirect, Symptoms of serious illness in babies and children

Last updated: July 2026. Sources include Red Nose Australia and Raising Children Network where cited above. This guide is general information only. For individual concerns, see your GP or child health nurse.