What to Expect at Each Age: Baby Sleep from 4 to 23 Months

“I don’t know if what my baby is doing is normal, or if something’s actually wrong.”

This is one of the most common things I hear from parents, and it’s a fair question. “Normal” changes so much between 4 months and 23 months that it can be hard to know what to expect. The sleep struggles of a 5-month-old can look completely different from those of a 14-month-old, and what’s completely expected at one age can be a sleep pattern worth addressing at another.

The comparison trap is real too. It’s very easy to look at someone else’s baby and wonder what you’re doing differently. Often, you’re not doing anything differently. The ages just don’t line up.

This guide walks through what’s typical at each stage from 4 to 23 months, the age range I specialise in supporting, so you can get a clearer picture of where your baby is right now and what, if anything, you may want to work on.

And one thing I want you to keep in mind as you read: every baby is different. The same sleep challenge can have very different root causes, which is why age alone doesn’t tell us the whole story.

One important piece of the puzzle is independent sleep skills. This simply means your baby can fall asleep and settle back to sleep with little or no hands-on help from you. It doesn’t mean they will never wake at night or need you. It means they have a skill that can help them navigate the many changes that come with the first two years.

With that in mind, here’s what you can generally expect at each stage.

4 to 6 Months: The Foundation Window

This is an important window in your baby’s first year because so much about their sleep is starting to change. Their sleep is becoming more organised, and they are becoming increasingly capable of learning to settle independently. This makes 4 to 6 months a great time to start building the foundations for independent sleep.

What’s happening: Around four months, your baby’s sleep architecture matures and their circadian rhythm is becoming more established. This is often when parents notice that the newborn days of sleeping anywhere, anytime seem to disappear. As your baby starts experiencing more distinct sleep cycles, the way they fall asleep can start to matter more. They may begin to rely on the same conditions when they wake between sleep cycles.

What’s normal: Night wakings and night feeds are still common at this age. Some babies are capable of longer stretches of sleep, while others still wake to feed overnight. There is a wide range of normal.

What to watch for: If your baby is waking every 45 to 60 minutes throughout the night, needs to be nursed, rocked or held every time they fall asleep, or is consistently struggling to get enough restorative sleep, it is worth looking at how they are falling asleep and whether they have started relying on one or more sleep associations.

What to focus on: This is a great time to start giving your baby opportunities to learn how to fall asleep independently. You don’t need to wait until sleep becomes a major problem before introducing healthy sleep habits.

Focus on a predictable bedtime routine, consistent nap timings, an appropriate sleep environment, and giving your baby opportunities to practise falling asleep independently, rather than always needing your help to get to sleep.

Typical sleep needs: Around 12 to 16 hours in 24 hours, including naps. Many babies are still taking 3 naps a day, with the transition toward 2 naps usually happening over the following few months.

6 to 9 Months: Separation Anxiety and Changing Sleep

What’s happening: Your baby is becoming increasingly aware of the world around them and of the people they rely on. Separation anxiety may begin to emerge during the second half of the first year, and for some babies, this can show up more noticeably around bedtime or during the night.

Your baby is also becoming much more mobile and curious. Crawling, sitting, pulling up and exploring their environment can mean there is suddenly a lot more happening in their little world.

What’s normal: You may see some temporary bedtime resistance, an increased need for reassurance, or disrupted sleep during periods of rapid development. Your baby may suddenly seem to need you more at bedtime than they did a few weeks ago.

What to watch for: If your baby has been sleeping reasonably well and suddenly begins waking frequently throughout the night or spending long periods awake overnight, especially if this continues beyond a temporary phase, it’s worth looking at what’s changed.

Sometimes a sleep association that was manageable before becomes much more disruptive as your baby develops and becomes more aware of their surroundings.

What to focus on: Consistency becomes especially important at this age. During periods of separation anxiety, your baby may look for more reassurance at bedtime: Are you still there? Will you come back?

A predictable bedtime routine, a consistent response to night wakings, and a familiar sleep environment can give your baby the security and predictability they need.

Typical sleep needs: Around 12 to 16 hours in 24 hours, including naps. Most babies this age are moving toward 2 naps a day.

9 to 12 Months: New Skills, New Sleep Challenges

What’s happening: Around 9 to 12 months, your baby is learning an incredible amount. Pulling to stand, cruising, possibly beginning to walk and developing new communication skills can temporarily make settling and sleep more difficult.

With all these new skills developing, it’s also common for parents to wonder whether their baby is starting to need fewer naps.

What’s normal: A temporary period of disrupted sleep while your baby is learning a new skill is common. You may see more difficulty settling, shorter naps, or an increase in night waking while your baby is busy practising something new.

These periods can be frustrating, but they don’t necessarily mean that your baby’s sleep has suddenly “gone backwards.”

What to watch for: If your baby is consistently taking only one short nap during the day, regularly waking very early and being unable to resettle, or waking frequently overnight when they previously slept well, it’s worth taking a closer look at their schedule and sleep habits.

What to focus on: Don’t rush the transition to one nap. Many babies are still taking two naps at this age. The transition often begins around the first birthday, with many children showing clearer readiness around 13 to 14 months, although there is plenty of individual variation.

Rather than focusing on the age alone, look at the overall pattern of naps, bedtime and overnight sleep. Your baby’s individual sleep needs and how well they are coping with their current schedule will give you much better clues about whether they are ready for a change.

Typical sleep needs: Around 12 to 16 hours in 24 hours, including naps. Most babies at this age are still taking 2 naps a day.

12 to 18 Months: The One-Nap Transition

What’s happening: The move from two naps to one is one of the bigger sleep transitions of the first two years, and it often catches parents off guard because it doesn’t happen overnight.

Your toddler may refuse the morning nap one day, then happily take it the next. They may seem ready for one nap, only to become completely exhausted by late afternoon when you actually make the switch. The transition can take several weeks, with good nap days and difficult ones along the way.

What’s normal: As your toddler gets closer to being ready for one nap, you may notice that the morning nap becomes harder to achieve, takes longer to settle for, or starts pushing the afternoon nap too late.

You may also have days where your toddler still needs two naps and other days where they manage well with one. This doesn’t necessarily mean they are ready to make the switch permanently.

The goal isn’t to rush your toddler into one nap. It’s to gradually shift their schedule as they become ready, while making sure they are still getting enough daytime sleep.

What to watch for: If your toddler is regularly taking a very long time to fall asleep at bedtime, waking extremely early in the morning, consistently skipping naps and becoming overtired, or suddenly having much more disrupted night sleep, their schedule may need some adjustment.

Sometimes the transition is overdue. Other times, the move to one nap has happened too quickly.

What to focus on: When your toddler is showing consistent signs that they are ready, gradually move the nap later toward the middle of the day, eventually aiming for around 12:30pm.

You don’t have to make the change all at once. Gradually shifting the nap later gives your toddler’s body time to adjust to the longer stretch of awake time in the morning.

As the nap moves later and consolidates into one longer nap, bedtime may need to move earlier temporarily to compensate for the lost daytime sleep. Pulling bedtime too late during this transition leads to overtiredness and worse overnight sleep.

Typical sleep needs: Around 11 to 14 hours in 24 hours, including naps. Once established, one midday nap is often around 1.5 to 2.5 hours, although individual sleep needs vary.

18 to 23 Months: Toddler Independence and Bedtime Boundaries

What’s happening: Your baby is now well and truly a toddler. They have opinions. Strong ones.

At this age, toddlers are becoming increasingly independent, and bedtime can become one of the places where they start testing those new-found independence skills. They understand much more than we often give them credit for, and they are very good at discovering which requests might buy them another five minutes before bedtime.

What’s normal: Some bedtime negotiating is completely normal. One more drink of water. One more story. One more hug.

You may also see temporary periods of disrupted sleep during developmental changes or periods of increased separation anxiety.

What to watch for: If your toddler is consistently taking more than 30 to 40 minutes to fall asleep, waking frequently overnight after previously sleeping well, regularly refusing their nap and becoming overtired, or repeatedly trying to get out of their cot, these are patterns worth looking at.

It’s also worth remembering that most toddlers are not developmentally ready to permanently drop their nap at this age, even if they start resisting it from time to time.

What to focus on: Boundaries and consistency are your best tools at this age. A clear, predictable bedtime routine gives your toddler the security to wind down, while a consistent response to bedtime requests and night wakings teaches them what to expect.

And don’t underestimate the power of simple explanations. “It’s time to sleep. Mummy and Daddy will be here when you wake up.” Your toddler may understand far more than you think.

Typical sleep needs: Around 11 to 14 hours in 24 hours, including naps. Most toddlers this age are still taking 1 nap a day, often around 1 to 2 hours.

So, What’s Normal for Your Baby?

Wherever your baby or toddler falls on this timeline, what matters most is understanding what’s developmentally normal for their age and recognising when a sleep pattern has become difficult for your family.

The goal isn’t for your child to never wake during the night. It’s to help your child develop the skills to fall back to sleep independently when they do.

Not every night waking is a problem. Not every short nap needs fixing. And not every difficult phase means you’ve done something wrong. But “it’s normal” doesn’t always mean you simply have to wait it out.

Every baby is different, and the same sleep challenge can have very different root causes. Sometimes it’s a schedule issue. Sometimes it’s a sleep association. Sometimes it’s a developmental phase. Often, it’s a combination.

This is why independent sleep skills are so valuable. A baby who can fall asleep independently and settle back to sleep has an important skill to draw on through developmental changes, nap transitions, illness, travel and the many disruptions that come with the first two years.

It doesn’t mean they will never struggle with sleep again. It means they have the skills to better navigate those changes when they come.

If you’re unsure whether your child’s sleep is simply a developmental phase or a pattern that needs a closer look, that’s exactly what I’m here to help you work through.

Book a free 20-minute discovery call and let’s talk about what’s happening with your baby’s sleep and how we can work towards better sleep for your family.