wonder weeks app

Wonder weeks chart: Lets look at wonder weeks and how these affect your baby and toddler sleep.

Wonder weeks chart: Lets look at wonder weeks and how these affect your baby and toddler sleep.

Unless you have been living under a rock for the last few years, you will no doubt have heard of the wonder weeks book or the wonder weeks app.

The authors of this book (wonder weeks) compared observational studies of infant chimps to the hierarchical perceptual control theory developed by William T Powers, did further human observations and wrote the book the wonder weeks.
Wonder weeks refer to leaps in mental developmental and are hypothesised to be linked to grumpy periods or regressions.
In total there are 10 leaps over 20 months, and the wonder week authors explain that each leap may be preceded by a fussy, grumpy or clingy period in your babies mood and temperament.

Knowing this for some people can be empowering, they are confident their baby is not sick, nothing is wrong, they are simply developing.

For other parents this knowledge can bring feelings of anxiety and dread, and for these parents, I recommend deleting the app, returning the book to the library and just enjoying your baby!

Your baby is a baby, not a robot, so they will have fussy grumpy period, but you are a fantastic parent and will no doubt respond accordingly.
We have found the sooner our clients establish healthy sleep habits and predictable routines, the easier they navigate fussy stages, and minimise any periods of unhappiness.

This is due to parents being able to confidently read cues within the context of what they know their baby needs or does not need.
If you have a regular routine, and your baby can easily self-settle and you hit “stormy period week x” you’ll know if your baby is just grumpy, or is getting grumpy because a nap is due, a feed is due, or conversely if they just need a change of scenery.

You wont be second guessing your nap routine, or how much sleep your baby needs. Having this predictability helps you to meet your babies changing needs before they’re crying and fussy.
Lots of clients tell us they worry about the wonder weeks and their affects on sleep. But while we know that new brain synapses are forming, skills are being mastered, and brains are busy working away, we also know that sleep is paramount for these skills to be moved from short term to long term, and your baby can continue to sleep well through these wonder week leaps, and most do, especially once those predictable sleep patterns are established.
The only notes I can find in the wonder weeks book on sleep, say virtually the same things for every leap.

  • Less sleep
  • Nap strikes
  • Early wakes
  • Delayed onset of sleep


Now while this certainly covers pretty much any sleep blip, as a parent reading the wonder weeks book I felt this wasn’t a book to help me with sleep, but just to understand development and fun ways to encourage this development.
Below you will find a guide on what happens to your baby’s sleep, during these wonder week leap periods, and some helpful tips.

So do your mum friends a solid and share this with them if they’ve ever mentioned the wonder weeks app to you.

Wonder week leap 1

5 week old (1 month) 
New-borns are born with a level of melatonin from their mothers, this makes a lot of new-borns relatively sleepy in those first few weeks.

As it wears off your baby will “wake up” to the world and this can start to present issues with settling if you previously managed to just pop baby down and they slept thanks to the flood of maternal melatonin.

Try hands on settling techniques and experiment with different styles to see what works best for your baby.

Wonder week leap 2 

8 weeks old (2 months)
Crying peaks in new-borns between 6-8 weeks of age, so this can be a tricky time for many families. Cluster feeding is on its way out, and your baby might be craving an earlier bed time routine and more sleep pre midnight if they were previously a cluster feeder.

By 8 weeks new-borns are happy to stay awake for up to 1.5 hours between naps, and sometimes parents don’t realise how quickly their babies awake window increases and may be trying to settle an under tired baby.

Ensure your new-born is making good weight gains each week, as a hungry baby will be a fussy baby who doesn’t sleep well.

Wonder week leap 3 

12 weeks old (3 months)
Your baby’s circadian rhythm is pretty much fully formed, they know the difference between night and day, and this is a great age to work on consistent naps, establish a nap routine and pre sleep ritual to encourage independent settling when your baby is ready.

Many babies begin to outgrow being rocked and patted to sleep, and this can gradually start to frustrate not settle your baby. Some babies begin to roll from tummy to back, and may fight being swaddled.

Try transitioning to a one arm out wrap and a sleeping bag. Your baby is likely experiencing waking after 45 minutes as their sleep cycles are very obvious by this age, and you’ll need to start working on teaching your baby to go down awake to help with this. Try our mini guide to learn EXACTLY how to put your baby down awake, from newborn to 12 months!

Wonder week leap 4

19 weeks old (4 months)
Welcome to the 4 month sleep regression month.

If you hadn’t noticed sleep cycles of 45 minutes previously, you may well this month. Your baby is entering the period where they can begin to use their positive sleep associations to start to settle themselves to sleep and back to sleep. This can be an important skill to work on if you start to notice 2 hourly wake-ups at night. Re-settling when not hungry will help prevent reverse cycling, and encourage natural consolidation of night sleep.

4 month sleep regression

Wonder week leap 5

26 weeks old  (6-7 months)
The biggest month for sleep changes so far!

Starting solids affects the gut and how your baby feels with new bi products of food digestion.

Rolling both ways starts, and your baby might prefer to roll when it’s sleep time, and this can result in delayed settling, more crying when settling, and both mum and baby feeling frustrated.

You definitely need to un-swaddle if you haven’t yet, and this new found freedom can be a tricky transition. Dream feeds can disturb your babies most deep stage of sleep, and should be dropped in this age bracket too.

All these new skills mean new brain synapses forming, and can result in unsettled sleep periods, but be confident this is the ideal age to work on self-settling and encourage a long midday nap, and 6-8 hours sleep at night.

Wonder week leap 6 

37 weeks old (9-10 months)
By 8 months your baby has object permanence, they understand when you leave the room you still exist, this can lead to separation anxiety, which may disturb bed time settling. Try pop ins or sitting quietly while your baby settles to sleep.

Crawling is well established, and this is a big movement for your baby to grasp and babies love to crawl when they're meant to be sleeping!

When you baby crawls they have to change their eye focus from the ground to the horizon and this helps build new brain synapses. Combined with the crisscross body movement of arms vs legs means your babies brain has a lot to process come sleep time! 

Don’t try to force your baby to lie down in their cot if they are moving and cruising around. It’s normal for all babies to have to learn to lie down when they are tired in order to sleep. Your baby will be well established on 3 meals a day, and you can likely drop all night feeds if you haven’t already.

Wonder week leap 7 

46 weeks old (11-12 months)
The 12 month sleep regression is the biggest regression of them all in my opinion, but the one which requires us to “do” the least. Your baby might fight their morning nap, but most babies still need this nap despite refusing it for a couple of weeks.

Continue to offer the nap, and limit it to 15 minutes if the lunch nap starts to shorten. Your baby is learning to pull up to standing, walk, and say words, they understand consistent routines for set activities and you can use this to your advantage by having a nice relaxing pre sleep ritual before your naps and bed time.

Wonder week leap 8

55 weeks old (13-14 months)
By 15-18 months your baby will drop to one nap, the month preceding this can be a bit messy with your baby sometimes taking their morning nap and sometimes skipping it.

Your baby will be very physical and being physically tired they still need 11-12 hours sleep at night but may start to show you some push back as they test their independence out on you. Have consistent routines and allow your mini toddler plenty of time to wind down to prepare to sleep at night. Stories and quiet time.

Wonder week leap 9

64 weeks old (16 months)
If you have great sleep habits established you should make it though these months relatively unscathed…..you may however need to start saying “no” as your toddler starts to test bed time boundaries.

Remember that crying out for milk at night is a boundary, and if you have previously night weaned, be consistent with your boundary and your toddler will quickly re-consolidate their night sleep.

Conversely early waking toddlers are also testing the boundary of calling out at 5am, and looking to see what the cause and effect relationship is here, do they get up and get to play? Or are they expected to go back to sleep?


Wonder week leap 10

75 weeks old (18 months)
Many parents are starting to be comfortable with discipline in the day at this age, but struggle to view tantrums around sleep to be the same as tantrums around getting in a car seat or sitting in a highchair to eat. Be consistent in your approach both day and night.

Your toddler will definitely be on one nap by this age and will begin to gradually over the next 12 months shorten his/her nap, and start to need slightly less sleep at night.

Separation anxiety can rare up this age, build confidence in your toddler by popping back to check on them at bed time, consider leaving the door open a little, avoid bed time stalling tactic with a good bed time routine.

This is a common age for a new baby to emerge on the scene and parents struggle with the juggle of a new-born and a toddler refusing bed time. Avoid this by establishing those boundaries and routines before the new baby arrives.
77 weeks old  (20 months)
You’ve made it through the busy 20 months.

There is however a 2 year sleep regression which is commonly associated with separation anxiety. Introduce a night light, try leaving your toddlers door open a little at bed time, and if need be sit with them while they fall asleep, but try to avoid climbing into bed with them unless you are happy to continue to do this long term.

Are you overwhelmed or intrigued to see these developments emerge in your baby?

Remember all babies experience these changes differently, and there is no better time to work on good sleep than the time where you are ready.

Don’t be put off thinking there is a new wonder week leap coming and sleep will fall apart or sleep training will be impossible.

All of our 60,000 clients have chosen to improve their babies sleep when the time was right for them and their family despite any impending wonder week leaps, and as you can see your baby will be growing, changing and developing so much in the first 2 years, it would be almost impossible to find an “ideal” window in that time.
Do you have the wonder weeks app or book?

How have you found it? Comment below, share your story with our community.


Emma Purdue

Emma is the owner and founder of Baby Sleep Consultant, she is a certified infant and child sleep consultant, Happiest Baby on the block educator, has a Bachelor of Science, and Diploma in Education. Emma is a mother to 3 children, and loves writing when she isn't working with tired clients and cheering on her team helping thousands of mums just like you.


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  • I love the app on my phone, it helps me know whats happening and why my boy is a bit off, but it hasn’t affected his sleep. I worked with Kelly and since then everything has been smooth sailing and he is 9 months now!

    Nicki on

  • I was nervous to sleep train because the stormy periods and leaps were always coming up, but it got to the stage where I couldn’t continue as I was, so I bit the bullet, worked with Cara and have never looked back!

    Fiona on

  • I have the wonder weeks app, but I found it stressful so I deleted it as I was worried about the storms before they even arrived.

    Sarah on

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