The Wonder Weeks is a parenting tool which shows you the developmental leaps your baby goes through and explains how these changes affect how they see the world, their abilities etc. In turn, this explains the changes in their behaviour. The beauty of The Wonder Weeks is that it lets you know when these leaps are going to happen and so is hugely reassuring. If your baby becomes unsettled, it is great to know that it isn’t your fault but is a perfectly normal phase they are going through. It is an excellent tool for keeping you sane! 

All babies go through fussy phases. You might be doing all you can to settle them, only to find them crying or being cranky for no apparent reason. The good news is that it isn’t your imagination – all babies go through difficult periods around the same age but how great would it be to get some warning that it’s coming? 

Research has shown that a baby’s development occurs in predictable jumps or ‘leaps’ and during this time, they will learn more than at any other. The problem is that with each leap comes a drastic change in your baby’s mental development, which affects not only his mood but also his health, intelligence, and sleeping patterns. It would be totally normal for your baby to be clingy and bad tempered! While the difficult behaviour can be a bit of a nightmare to deal with, you can rest assured it is actually a sign that great progress is underway. 

The Wonder Weeks was originally a book (and now an excellent app) based on this research. According to The Wonder Weeks philosophy, a baby should go through 10 of these leaps in its cognitive development during the first two years, in weeks 5, 8, 12, 19, 26, 37, 46, 55, 64 and 75.  


These mental developments can be upsetting for your baby. For example, newborns can only see black, white and a little bit of red.  Imagine how freaky it must be to suddenly see blue!!

I’ve used The Wonder Weeks myself and recommend it to all my clients.  So many people have told me how helpful it is. It’s wonderful to know that your baby might just need extra cuddles for a few days and takes away the worry that you might be spoiling them or not giving them what they need. Use your instinct, understand that each day will be different and know that that is totally fine. 

What are the 10 Mental Leaps?



Leap 1 – Wonder Week 5 - Changing Sensations

In this first leap, your baby’s senses are more sensitive than they were immediately after birth. It is not so much the sensations themselves that are changing, but rather the baby’s perceptions of them.



Leap 2 – Wonder Week 8 – Patterns

Sometime around 8 weeks your baby will begin to experience the world in a new way. He will be able to recognise simple patterns in the world around him and in his own body. For example, when they have a tummy rumble, they can see the pattern of tummy rumble = fart and can begin to predict it coming. 



Leap 3 – Wonder Week 12 – Smooth Transitions

Leap 3 affects your baby’s ability to perceive the way things change around him—such as a voice shifting from one register to another, the cat slinking across the floor, and the light in a room becoming dimmer as the sun dips behind the clouds.



Leap 4 – Wonder Week 19 – Events

At leap 4 your baby is beginning to learn that experiences are split up into familiar events. For example, if we see someone drop a rubber ball, we know that it will bounce back up and if someone jumps up into the air, we know that she is bound to come down. 


Leap 5 – Wonder Week 26 – Relationships

One of the most significant relationships that your baby can now perceive is the distance between one thing and another. For a baby, it is an alarming discovery and a very radical change in his world. They become very very clingy at this stage (Not a good time to start anything new!)



Leap 6 – Wonder Week 37 – Categories

Your baby is now able to recognise that certain objects, sensations, animals, and people belong together in groups or categories. For example, a banana looks, feels, and tastes different to spinach, but they are both food.



Leap 7 – Wonder Week 46 – Sequences

You may now see your baby looking first to see which things go together and how they go together before trying to put them in each other, pile them on top of each other, or piece them together.



Leap 8 – Wonder Week 55 – Programmes

Every child’s first birthday is a significant occasion. The end of the first year means for many parents the beginning of the end of babyhood. Your little cherub is about to become a toddler.



Leap 9 – Wonder Week 64 – Principles

For the first time, your child is now able to change programs he’s learned so far and the resulting consequences of this.


Leap 10 – Wonder Week 75 – Systems

At Leap 10 your child starts to understand that he can choose how he wants to be:honest, helpful, careful, patient etc. 

I recommend downloading The Wonder Weeks app to get much more information and advice on all of these stages of your child’s life. Do it now, and have it ready on your phone for when your baby gets here. One bit of advice from me, however, is to pay attention to your child’s starting point. My own child hit each milestone a week earlier that predicted in The Wonder Weeks chart – but once you’ve worked it out you can follow it all smoothly.

Edinburgh Lothians Baby Newborn Photographer Wonder Weeks Development Mental Leaps Phases Research Progress Diana Baker Photography