You believe your baby is developing the right skills at the right time, but how can you be completely sure? Do you find yourself comparing them to other babies? Or do you simply let them develop at their own pace?

We know that it can be tricky trying to track your child’s progress as they get older. But don’t worry! We’re here to take you through a guide to major milestones in each area of development and explain what your child should be able to achieve by the time they’re 4–8 months old.

Just a quick reminder: children develop at their own pace! Please don’t overthink or stress if they’re not meeting these milestones the moment they turn 4–7 months old. These are guidelines; they’re not set in stone.

So, let’s begin with their physical appearance and growth.

Physical appearance and growth:

During these few months, your baby will grow about 5 cm (2 inches) in length, and their head circumference will increase by about 2.5 cm (1 inch). On their 8-month birthday, they should weigh roughly 2½ times their birth weight. As their body grows, they’ll begin to look more and more in proportion to their still somewhat large head.

Their movement:

During these months, your baby will achieve a great challenge: sitting up all on their own! They’ll accomplish this as they use and strengthen their neck and back muscles. Initially, they will only raise their head when they’re lying on their stomach and something passes their line of vision. Practising some tummy time every day will help these muscles develop.

What are the movement milestones?

Can roll back and forth (from their front to back and vice versa).

Sits with the support of your hands and then manages to sit on their own.

Reaches with one hand.

Can support their whole weight on their legs.

Can transfer objects from hand to hand.

Uses all their fingers at the same time to pick up an object.

Visual development:

Your baby’s vision will advance greatly during these months. They’ll now see different shades of colour, see at further distances, and they’ll be able to follow faster movements. And they’ll just adore looking and babbling at themselves in the mirror.

What are their visual milestones?

Their distance vision will mature.

Their ability to track movements and moving objects will greatly improve.

They’ll develop full-colour vision.

Language development:

Previously, your baby responded to the tone of your voice more than anything else. A high-pitched voice made them smile, a soothing voice kept them from crying, and a shout of anger likely made them cry. After 4 months, your baby will start to hear the individual sounds you make and eventually notice that the vowels and consonants you use make words and sentences.

At 6 to 7 months, they’ll start to imitate your language and the inflections of your voice. Speak to them and repeat the noises they make, encouraging as much speech as possible. And don’t forget to read to them, sing to them, and listen to them. They’ll love hearing you chatter away.

What are the language development milestones?

Responds to their own name.

Starts to respond to “no”.

Babbles chains of consonants.

Responds to sound by making sounds of their own.

Uses their voice to display pleasure and displeasure.

Distinguishes emotions by tone of voice.

Cognitive development:

While previously you may have wondered whether your baby was actually thinking and taking things in, now it’ll be quite clear that they’re not only fully absorbing information but applying it to their day-to-day activities too.

Somewhere between 4 and 5 months, they’ll begin to learn the concept of cause and effect. This will lead to a lot of experimentation, experimenting with the sounds objects make when they’re dropped or shaken. Make sure their environment safely allows for this sort of experimentation, with plenty of soft toys and unbreakable items and nothing that could act as a potential choking hazard.

By 7 to 8 months, your baby will also discover the permanence of items and people, slowly realising that they exist outside of their vision.

What are the cognitive milestones?

Explores objects with their hands and mouth.

Struggles to get objects that are out of reach.

I can find partially hidden objects.

Emotional development:

Between 4 and 7 months, you’ll notice your baby will go through a rather dramatic personality change. While at 4 months they’ll seem preoccupied with sleep, food, and affection, once they’re able to sit up and start to use their hands, they’ll become more assertive and attentive to the world around them. They’ll want to reach out and touch absolutely everything, and they might yell and drop objects to get your attention if they need help. While they may quickly tyre of toys, your attention will never prove boring!

What are the social and emotional milestones?

Enjoys social play.

Is greatly interested in mirrors.

Often appears joyful.

Responds to other people’s enthusiasm.

What are the things to look out for?

Every child is different and will develop different skills in their own time. However, it’s always a good idea to talk to your GP or paediatrician if your child is still showing these signs at 8–12 months old:

It seems very stiff; their muscles are tight.

It seems very floppy, like a ragdoll.

Their heads flop back when they’re placed in a sitting position.

They refuse to cuddle.

Only reaches for things with one hand.

Shows no affection for their carers.

Doesn’t enjoy being around people at all.

Their eyes consistently turn in or out.

Doesn’t respond to noises around them.

By 4 months, they do not turn their heads to locate sounds.

Persistent crying or eye drainage.

I can't roll in either direction from 5 months onwards.

It appears inconsolable at night after 5 months.

Has difficulty getting objects to their mouth.

Does not smile spontaneously at 5 months.

Doesn’t babble by eight months.

I can't sit with help for 6 months.

Doesn’t laugh or make squealing noises by 6 months.

By 6 to 7 months, they do not reach for objects.

Can’t bear some weight on their legs by 7 months.

Shows no interest in games of peekaboo by 8 months.

They don't try to attract attention through their actions for 7 months.

Doesn’t follow objects with both eyes at close and far distances (by 7 months).

What are the developmental milestones for 4 - 7 months?

On Unii’s Baby Development Journey, we look at the development milestones for 4–7 months.