Baby development and milestones: your 4-month-old

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Your 4-month-old baby is becoming more curious, adventurous, and quite the taster! So here's what you should be prepared for now.

Your little munchkin is now a “big” 4 month old and is perhaps in the most beautiful stage of his life. By now he is more expressive, and you will often notice him smiling, cooing, and laughing incessantly. How cute!

Also, don’t be alarmed if he tries to raise his head while laying flat on his tummy. It’s just a way to let you know that your lil’ bub is trying new things and growing up fast.

As a new parent you will also see many new physical changes in him.

By the fourth month, a baby doubles his birth weight and you probably won’t be able to stop yourself from pulling those chubby cheeks.

But this is also a time time when you’ll have to prepare yourself for an emotional rollercoaster – so much so that that joy and pride he’ll give you will have you reaching for the tissues.

What is going to happen, you ask? Well, here are a few critical changes you will witness in your bub as soon as he hits this month!

4 month old

Your 4 month old baby is a ball of cuteness!

Your 4 Month Old Baby’s Development

Physical Development

In his fourth month, your baby’s physical development will be faster than you’ve seen so far. He should be double his birth weight, as we mentioned. But not just that.

Steadying the Head

You’ll also notice him trying to keep his head steady, unsupported. If your little explorer is super active, you will also see him trying to push his legs down whenever his feet are on a hard surface.

Twisting and Turning

Since he is just learning to move more frequently by this month, you’ll be running for your video camera to capture the moment he turns from his tummy to his back and vice versa. Right now, you’ll see him trying to bring his hands to his mouth, and even push his elbows up while lying on his tummy.

Tasting and Learning

At this stage, anything that your baby can pick up will likely end up in his mouth. So if you do have a dangling toy or one that makes noise, rattles, or even lights up, your baby will try to hold on to it, shake, fling it, and put it in his mouth. In fact, you might want to be prepared because it could also be your hair!

Remember that when you hold your baby, make sure to remove sharp jewelry pieces from your ears and even necklaces because if they’re shiny. Trust us, he’s going to want to pull it and put it in his mouth. He will do this primarily because he is becoming more dexterous and using more of his hands.  

Heightened Senses

By this time, your baby’s eyes will move together and also be able to focus better on any particular moving or bright object. This is because his vision will now reach 20/40. He’ll also be able to pick up colours and contrast. So if you notice that your baby is still not able to move both his eyes together or seems to be cross-eyed, report it to the pediatrician.

4 month old

Your little one’s sleep should slowly start getting more stable.

Stable Napping Schedule

And now some good news!

By his fourth month, your tiny munchkin will also adapt a stable napping schedule. This means, you’ll both be able to enjoy a full-night’s sleep. Typically, a baby sleeps for seven to eight hours by this time. And if you factor in one or two naps, you’ll see him sleeping for a minimum of 12 to 13 hours per day.

So congratulations, you can have your sleep back now!

Cognitive Development

While you notice all these physical changes in him, you’ll also be surprised to notice his fast cognitive development during this month.

More Expressive

As soon your little one turns four months and his abilities to express himself will heighten, he will be able to tell you if he is happy or sad more easily.

More Responsive

This also means that he will respond to your affections more often. So when you call out to him he may look at you and smile, in recognition or your affection for him.

Better Hand-Eye Coordination

Also, his hand and eye coordination will have improved by this time. So this means he will spot objects and reach for them more effectively. Since his motor skills have developed further, you will also notice him spotting an object and moving his eyes along with it.

But the best part is the fact that he will be able to recognize those around him. So call out his name because he is listening to you and knows you are talking to him.

Social and Emotional Development

As far as your baby’s emotional and social growth is concerned, you’ll be super happy to notice some new developments this month. Since your baby is now old enough to express and respond to emotions, he’ll smile more frequently now. Now, won’t that just make your day?

But a response to your emotions and a heightened ability to express also come with their fair share of tears.

If you love playing with your baby and suddenly stop, you may upset him. But worry not, this is new to him, too. By this age, he will love to play and may let you know when he wishes to stop or continue.

Also, rest assured, if you make faces at him, don’t be alarmed if he tries to mimic the same. By this cute age, babies tend to imitate what they see. And that includes making faces.

After all, he got it from his mama!

4 month old

Your 4 month old cutie is getting very expressive! | Image source: Shutterstock

Speech and Language Development

In trying to understand how he may behave or develop, let’s not forget that your little bub is going to pick up everything from you.

So when you call your baby “my little munchkin” in that cutesy sing-song voice, know that your baby will try to copy what he just heard – although not exactly. He will also start babbling by now.

To encourage your baby’s language skills, try to talk to your little one just as you would with an adult. Research has shown that adopting a sing-song voice is good for babies. It helps them learn how to speak faster.

You must also use complete sentences and proper grammar. Throw in phrases such as “please” and “thank you.” Even if your tot doesn’t fully comprehend their meaning, he’ll be able to understand the context and draw parallels between the words and their meaning in the future.

Health and Nutrition

Ideally, doctors advise that a baby be breastfed until six months and start solids only after that. But sometimes bigger babies may not feel satiated with breastmilk or baby formula.

So what do you do in this situation?

Well, if your doctor gives you the go-ahead and your baby is able to hold his head steady and sit, you can start solid foods by the fourth month. But remember that your baby’s first food should ideally include iron and should be mixed with breastmilk or formula.

Our advice is that you should prepare the iron mix in the same consistency as the formula so that your baby gets used to it. Gradually increase the thickness based on your baby’s ability to eat and digest.

Tips for Parents

Your little munchkin has only just begun his explorations. And since he is likely to pick up anything within his reach, try to make that item as safe and baby-friendly as possible.

Give Textures to Play With

Provide your baby with lots of textures to explore such as books and soft toys. There are chances he might ditch that and pick up a spoon instead, so let him have a wooden one instead. Just make sure the item is not too small for him to swallow and not too big that he hurts himself. Most importantly, have him close by you (while playing) at all times.

Sing and Talk to Baby More Often

By this age, your baby will also learn to hold his head steady, so plonk him on your lap and sing, play with him or even read him a book. Trust us, he will love to listen to your soothing voice. By now he is also slowly learning to look at you carefully and shower you with lots of smiles.

Childproof the House

Start preparing for a baby who is ready to move around the house. You can add gates to stairways, lock the cabinets, and keep wires away from the floor.

Other than that, enjoy this beautiful phase in your and your baby’s life and let him be a little explorer.


Previous month: Baby development and milestones: Your 3-month-old

Next month: Baby development and milestones: Your 5-month-old

Republished with permission from: theAsianParent Singapore

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