Congrats, parents! Your baby is almost halfway through their infant stage.
Between the ages of 4 to 6 months old, they are slowly but surely reaching the next milestones.
Now that they are a little bit older, they can do new things like reach for things, sit up on their own and even laugh.
As a new parent, you may be wondering what other achievements await them as they grow towards toddlerhood by the end of their first year.
Here’s what to expect in your child’s physical, cognitive and emotional progress between the ages of 4 to 6 months old.
Physical Development
Now that your baby is almost half a year old, they should be gaining around 2 kilograms per month in weight. In terms of height, they should be gaining around 1.3 cm in length per month.
By the end of their first 6 months of life, their overall height will probably be between 68 to 74 centimeters. Here are some other physical milestones they are expected to reach before this time.
Primitive Reflexes
At 4 months old, your baby will gain new reflexes and lose old ones. Old reflexes that will slowly fade soon include the moro reflex or the startle reflex. Babies typically develop this in the womb and continue to have them until 4 months old.
The moro reflex is a self-protection mechanism that happens involuntarily to help prevent babies from falling by instinctively reaching out for their caregiver. It usually activates during sleep; the infant startles awake and may cry.
The asymmetric tonic neck reflex (ATNR) or fencing reflex will also disappear around 6 months old. When your baby’s head is turned to one side, their arm and leg on that side extend, while the opposite arm and leg flex.
The fencing reflex helps develop hand-eye coordination and is sort of a practice run that helps your baby to roll over on their stomachs.
New Reflexes
By the time they reach 6 months old, the asymmetric tonic neck reflex is replaced with the symmetric tonic neck reflex (STNR). However, don’t be alarmed if your baby hasn’t reached this milestone as some babies take longer, typically until 9 months.
STNR is triggered when your baby moves their head up or down. When the head tilts forward, the arms bend while the legs extend. When the head tilts backward, the arms straighten while the legs bend.
This reflex is important to help babies transition from lying to crawling. It helps them push up on their hands and knees.
By 6 months old, their grasping reflexes (ulnar-palmar grasp and radial-palmar grasp) would be fully developed and will soon give way to more voluntary grasping. These grasping reflexes occur involuntarily when you put something into a baby’s hand.
Here are some other reflexes that are improving or changing:
- Swallowing reflex: starts appearing
- Parachute reflex: starts appearing (when the baby is turned face down towards the ground, their arms will extend as if to catch themselves.
- Blinking reflex: becomes well established
- Sucking reflex: becomes voluntary
Rolling Over and Sitting Up
At 4 months old your baby should be able to hold your heads up without support. Their head control will also improve. At 6 months old, your baby is strong enough to pull themselves up into a sitting position without support.
This sitting position is called ‘tripod sitting’. This is where they sit with legs spread apart with both hands touching the floor. This marks an exciting new milestone in not only their physical but also cognitive development.
They are also able to reach out for things and hold them with both or either hands. When given a rattle, they are able to shake it, knowing that it produces a sound (more about this under cognitive development).
Rolling over is also another exciting achievement that your baby will unlock during these stages. Your baby will slowly begin by rolling from their stomachs to their backs. Then they’ll slowly learn to roll from back to front. This newfound mobility strengthens their muscles, paving the way for a wider exploration of their surroundings.
Oral Exploration
Now that your baby can reach for and grasp objects on their own, their ‘mouthing’ behaviour will be more frequent. This is a normal part of growing up and is just a natural way for babies to understand their environment by ‘tasting’ the object.
Your baby’s oral exploration may overlap with their teething. So mouthing slowly becomes a way to self-soothe more than it satisfies curiosity. Biting on objects provides relief from teething discomfort. You can get them proper teethers for this when you start seeing their little chompers peek through.
It is important for parents to be particularly vigilant once their baby has mastered voluntary grasping. Supervise them and make sure they do not reach for any dangerous objects that they can put into their mouths. Toys need to be sanitised and cleaned properly to maintain utmost hygiene.
Cognitive Development
Between the ages of 4 to 6 months your baby is developing new sensorial and vocal skills. They are able to recognise shapes and faces and their sense of object permanence.
Your baby is now able to make more diverse sounds with their mouths and can remember things better.
Memory and Recognition
As their memory improves, their ‘object permanence’ also develops. This is the understanding that objects continue to exist even when they are not visible.
This is one of the reasons why babies enjoy peek-a-boo games so much.
At 4 months old, your baby can now remember simple events and familiar routines. They’ll get excited when they know it’s feeding time, or when a fun song plays on the TV.
You’ll find your baby will start remembering familiar people and objects even if they appear different, upside-down, in photos, etc. They’ll even look around for you when they can’t see you.
This all lays an important foundation for their emotional and social experiences later on.
Babbling
Your baby’s language development also takes a significant leap forward. While they still can’t form sentences your babies can now use more sounds when they babble.
From just being able to vocalise vowels (ah, eh, uh) your baby now start using consonants and consonant-vowel combinations such as ‘ba-ba’ or ‘da-da’
This babbling is an important precursor to speech, as it reflects your baby’s experimentation with sounds and vocalisations. They also begin to respond to their names and recognize tones of voice, distinguishing between happy, soothing, or angry speech.
You may even be surprised when your baby is able to respond to their names and simple instructions like ‘wave bye-bye’.
Environmental Awareness
Your baby is now becoming more and more aware of their surroundings. As mentioned, now that they are able to sit up, their cognitive development accelerates threefold.
Sitting up allows them to free their hands which expands their ability to interact with the world around them and not just simply observe passively. They can now engage in interactive play with their caregivers, touch and feel objects and even play with toys.
They now engage in what is known as trial and error problem solving. This is where they experiment with how objects react when shaken, dropped or thrown.
All of these further improve their cognitive skills such as hand-eye coordination, depth perception and problem-solving. Your baby may also show a certain level of interest towards vibrant and colourful patterns or objects.
Emotional Development
Your baby is now able to interact more actively in social situations. They’ll have more complex emotions, and are able to self-soothe.
They’ll also enjoy spending time with their caregivers now more than ever and can interact minimally through babbles, smiles and laughter.
Emotional Diversity
Your babie’s emotions have now advanced from simple joy, anger and sadness to frustration, distress, and surprise. You’ll start to be able to distinguish their emotional states better too by looking at their facial expressions.
They learn these new emotional reactions by observing their parents’ own emotional experiences. Now that they are 6 months old they become more and more sensitive to their emotional environment.
They are able to recognise and respond to your emotions and words. They can tell the difference between different facial expressions and tones of voice, which influences their own responses.
For example, a soothing tone may calm them when they’re upset, while an angry tone might cause them distress. This sensitivity to emotional cues is foundational for developing their empathy and social understanding.
Communication
At 4 months old, your baby craves attention and will try to communicate with you all the time through their simple vocalisations and noise. They probably enjoy lots and lots of eye contact too and will respond with smiles or laughter.
When you talk to them, or show them attention they can reply or respond with sounds and babbles. They may even laugh and smile. Back-and-forth interactions become more common even if it’s just in the form of babbles
Your baby will also show a preference for their parents or for certain familiar people. They may even show an interest in other babies when they meet them. By 6 months of age, they will start to feel wary or uncomfortable around new people.
But true ‘stranger anxiety’ will not start to appear until 7 to 8 months of age.
Emotional Regulation
At 4 months old your child still needs plenty of reassurance when they go through their emotional ups and downs. That is why they still need you at times to help them with their emotional regulation.
They’ll calm down when you speak to them or pick them up.
However, as they gradually reach 6 months old they’ll be able to learn self-soothing skills on their own most of the time. They might suck their thumbs or hold onto a favourite blanket or toy for comfort.
This is an important development in their ability to emotionally regulate themselves. Parents lay the groundwork for this by constantly maintaining a peaceful and safe environment in their home.
Slow and Steady
The 4 to 6-month period is a dynamic phase of infant development. Your child is slowly but surely reaching exciting goalposts in their physical, cognitive and emotional progress.
Each milestone is interconnected, collectively laying the groundwork for future developments. Parents can continue to support their child’s development by providing lots of physical activity, a safe environment for exploration, and plenty of social engagement and bonding.
as your baby is now able to communicate to you, you’ll be able to respond to their wants and needs more effectively.
Disclaimer: The information provided in this article is for informational purposes only and should not be considered as medical advice from Mamahood. For any health-related concerns, it is advisable to consult with a qualified healthcare professional or medical practitioner.
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