Your baby was sleeping beautifully… and then suddenly they learned to roll.

Or crawl.

Or pull themselves to standing.

And seemingly overnight, sleep has completely changed.

They're practising their new skill in the cot, taking longer to fall asleep, waking more frequently overnight or suddenly fighting naps they previously took without a problem.

Sound familiar?

Developmental milestones can absolutely disrupt baby sleep. And while it can feel like you've gone backwards, these periods are usually temporary.

Here's why new skills can affect sleep — and what you can do to help your little one through them without completely changing everything that was working before.

Why Do Developmental Milestones Affect Baby Sleep?

Your baby's brain is incredibly busy during the first few years of life.

When they're learning a new physical skill like rolling, sitting, crawling, pulling to stand or walking, their brain is working hard to process and practise that new ability.

And sometimes… they don't want to stop practising just because it's bedtime!

You might put your baby into the cot ready for sleep, only to watch them immediately roll onto their tummy, get onto all fours or pull themselves up against the cot rails.

They may even practise these skills during the night when they briefly wake between sleep cycles.

The result?

Sleep can temporarily become a little messy.

Signs a Developmental Milestone May Be Disrupting Sleep

You might notice:

• Suddenly taking longer to fall asleep

• Practising rolling, crawling or standing in the cot

• Becoming frustrated because they can get into a position but can't get back out

• More frequent overnight waking

• Shorter naps

• Fighting naps they previously took easily

• Waking earlier in the morning

• Becoming much more active at bedtime

• Calling or crying for you after practising their new skill

If sleep was going relatively well and one of these behaviours has appeared alongside a new developmental skill, there's a good chance the two are connected.

Rolling and Baby Sleep

Rolling is often one of the first milestones to cause parents concern around sleep.

Your baby may suddenly discover they can roll onto their tummy and want to practise it every chance they get, including in their cot.

Some babies love sleeping on their tummy once they can get themselves there, while others become frustrated because they haven't yet mastered rolling back.

Give your baby plenty of opportunities to practise rolling in both directions during awake time.

The more confident they become with the skill during the day, the less exciting (and frustrating) it tends to become at sleep time.

Always continue to place your baby down on their back to sleep and follow current safe-sleep recommendations.

Crawling and Baby Sleep

Before babies begin crawling, you may notice lots of rocking on all fours, pushing backwards, shuffling or practising movements in their cot.

It's almost as though their little brain is saying:

"I've just learnt something amazing and I need to practise it RIGHT NOW."

Even at 2am.

Again, lots of floor time and opportunities to practise during the day can help.

Try not to assume that a sudden nap refusal means your baby is ready to drop a nap or needs a major routine change.

Sometimes they're simply far more interested in practising their new skill than sleeping.

Standing in the Cot

This is a big one!

Your baby learns to pull themselves to standing and suddenly bedtime becomes:

Stand up.

Cry.

You lie them down.

Stand up again.

Repeat.

Often, the biggest problem isn't that your baby can stand, it's that they haven't yet learnt how to confidently get back down.

Spend plenty of awake time practising how to bend their knees and lower themselves safely from standing to sitting.

And when it comes to sleep time, try not to get caught in an endless game of repeatedly lying them back down.

Give them some space and opportunity to work it out themselves while continuing with your usual settling approach.

Should I Change My Baby's Routine?

Not necessarily.

When sleep suddenly changes, it's very tempting to start changing everything.

Maybe they need a later bedtime?

Maybe they're ready to drop a nap?

Maybe their awake windows need to be much longer?

Sometimes a routine adjustment is needed (particularly if your baby's sleep needs are changing at the same time) but we don't recommend making big changes based on a few difficult days.

First, ask yourself: Was their routine working before this new skill appeared?

If the answer is yes, we'd usually give things a little time before completely changing it.

Developmental disruptions are often temporary.

Give Them LOTS of Practice During the Day

This is probably one of the simplest things you can do.

Let them practise!

Lots of floor time gives your baby opportunities to master their new skill while they're awake rather than saving all their enthusiasm for the cot.

If they're learning to roll, practise rolling both ways.

If they're crawling, give them plenty of safe space to move.

If they're pulling to stand, help them practise getting back down again.

The quicker they become confident with the skill, the less novelty it tends to have.

Keep Your Response Consistent

When sleep suddenly becomes disrupted, it's natural to want to do whatever you can to get everyone back to sleep.

But if your baby previously settled independently and you suddenly begin rocking, feeding or holding them completely to sleep at every wake, those new sleep preferences can sometimes stick around long after the developmental stage has passed.

Of course, you can offer reassurance and support.

The key is to try to keep your response as consistent as possible with how you were settling before the disruption began.

What About Naps?

Developmental milestones can affect naps too.

Your baby may spend half their nap time crawling around the cot, pulling themselves up or chatting instead of sleeping.

If this happens, give them a reasonable opportunity to settle.

If the nap doesn't happen or ends up much shorter than usual, adjust the rest of the day as needed.

That might mean bringing the next nap forward, offering a small bridging nap or bringing bedtime slightly earlier.

One missed nap doesn't mean your entire routine needs changing.

How Long Does a Developmental Sleep Disruption Last?

There's no exact timeline.

Some babies barely seem affected by milestones, while others experience disrupted sleep for several days or a couple of weeks while mastering a new skill.

What we want to avoid is turning a temporary developmental disruption into a longer-term sleep pattern by changing everything too quickly.

If your baby's routine and settling were working before, consistency is often your best friend.

Developmental Milestones Don't Mean You've Gone Backwards. This is probably the most important thing to remember.

If your previously settled baby suddenly starts waking again when they're learning to crawl, stand or walk, it doesn't mean they've forgotten how to sleep.

They're developing.

Their little brain and body are busy learning something completely new.

Give them plenty of opportunities to practise during the day, keep their routine as consistent as possible and continue responding in a way that feels right for your family.

Most importantly, don't feel like you need to "fix" every difficult night.

Sometimes they simply need a little time to master their exciting new skill.

If you're unsure whether you're dealing with a developmental phase or whether your little one's routine needs adjusting, our age-specific Sleep Guides can help take out the guesswork.

Inside you'll find age-appropriate routines, awake times, gentle settling methods and practical troubleshooting for naps, night waking, early rising, regressions and more ✨