4-Month-Old Baby: Milestones, Development & Activities

Being a parent is indeed a blessing, and this realisation will be quite evident as your baby steps into his fourth eventful month. The disarming smile and the incoherent babble certainly make your world a more beautiful one! This period is filled with rapid growth and fascinating new skills, making it a wonderful time to observe and engage with your little one. Understanding 4-month-old baby milestones & development is key to supporting their progress. Check out this comprehensive guide to infant development at 4 months that details all its important aspects for you, from physical achievements to social and cognitive leaps.

Growth of a 4-Month-Old Baby

Every single month of your baby’s first year is time for quick growth when his brain and body are developing. If you are wondering how much a 4 month baby’s weight should be, simply double your baby’s birth weight to get a fair idea of an ideal weight. However, your baby’s weight gain is just one of the growth parameters. Speak to your doctor if you feel your baby’s face, thighs, arms, or bottom doesn’t have much flesh or fat and check what the growth milestones for a 4-month-old are (1).

4-Month-Old Baby Development

• When your baby first comes into this world, his vision is poor and not very sharp. By the fourth month, the clarity of vision improves, especially with respect to colours. You can introduce bright clothing and toys for the baby to appreciate them (2).
• When it comes to your baby’s vocabulary, it may seem like there is nothing much. However, if you pay close attention, you may notice him trying to mimic the words you say.

16-Week-Old Baby Development

Your baby is now able to create some vocal sounds on his own and understands them, too. Your little one may utter much-coveted words like mama or dada, though he may not understand the meaning. Remember, your child’s imitation powers are growing, and he will mirror your words and actions, much to your delight.

17-Week-Old Baby Development

Your baby will have doubled his weight by week 17, and his tummy is larger, too. If you are breastfeeding him, 6 to 8 feeds a day is enough. However, there will be many distractions now as he is alert to external sound and other stimuli. He will play with his hands and feet, use them to grab at things and can play alone for a longer time than before.

18-Week-Old Baby Development

Your baby will begin to laugh and giggle, although crying will still be his primary mode of communicating his needs. Funny faces, sounds, and peek-a-boo games will excite and generate smiles all around. He will love to explore and play with simple objects like a piece of cloth, a rattle, or a bell hanging over his baby crib. He is also able to distinguish between colours and shades and will show interest in coloured clothing, toys and books.

19-Week-Old Baby Development

Your tiny tot’s spine is straightening and gaining support from surrounding muscles. This will help him to hold his head and lift his shoulders when you pick him up. His vocabulary is growing too so you can prepare yourself for many incoherent babbling sessions that will go on for a while. Make sure you follow a routine that leads to slumber time. Feeding him, bathing him, reading a story to him or singing a lullaby can lead to a good night’s sleep for him and you, too.

4-Month-Old Baby Health

Your baby is now ready for the mandatory immunisations that a 4-month-old baby needs. It is also time to inform the doctor about any adverse reactions your baby has had from the initial vaccinations. Ensure breast milk or formula is his primary source of food. Take care of nappy rash by keeping the skin as dry as possible. Use warm water to clean the baby’s bottom while changing the diaper.

4-Month-Old Baby Milestones

The following are the important milestones your baby will achieve during his fourth month (3):

• Response to care and love: When you show love and affection to your baby, your baby will respond to it with a smile or a happy gesture. Your tiny tot now knows that kisses and caresses are equivalent to love and will react accordingly when you shower him with love. Your four-month-old baby is now able to understand love, especially when it comes from parents and siblings.
• Shows improved memory: Your baby’s recognition is better in the fourth month and will react towards specific toys and people, too. He may show his likes and dislikes in a defined manner, where he may love the company of his grandfather or resist being held by an aunt. He will be able to choose a favourite toy or a brightly coloured ball from a large and growing collection.
• Displays emotions: Just as your little one understands love, he is also able to express sadness when he enters the fourth month. He will cry when he doesn’t see you around or when he sees you walk out of the room. He will stop crying when he sees you coming close. The wail of sadness will be different from the cry of hunger, and you will be able to distinguish between them.
• Holds a steady head: When you hold your baby in your arms, he will be able to hold his head without any support. This happens because his neck muscles are a lot stronger, due to which he is able to make natural movements. Also, notice how he holds his head when you pick him up from a horizontal position.
• Develops stronger muscles: When you place your baby on his stomach, he will look to push his elbows downwards. Your baby’s upper arms are developing stronger muscles, and so are the back and shoulder muscles, which help him to do that.
• Can roll over: Your baby now has an increased range of movements at his disposal, which allows him to roll over from tummy to back. This is a huge step in his physical development, which is mostly due to the growing strength in his shoulders and back.
• Will laugh and smile: The fourth month brings a lot of giggles and laughs, which are accompanied by a flurry of hand and leg movements. Anything that your baby will find funny and interesting, like a sudden movement or an amusing sound, will elicit laughter and gurgles.

Behaviour of a 4-Month-Old Infant

By the fourth month, the baby will be able to connect to you and the rest of the family, too. Your baby will respond to other siblings in the same manner he responds to you. He is learning who to trust and who to turn to when he needs certain things. It is best to keep your little one away from television and other digital content, as he does not need this kind of stimulation. You and the rest of your family are enough to provide the brain stimulation he needs at four months.

4-Month-Old Baby Activities

Choose from any of the following activities for a 4-month-old infant that will help develop and keep your little one engaged. These four months’ baby activities are ideal to allow the baby to spend some time on his own and will provide a break for you, too (4).

1. Place a small soft toy on your child’s chest and watch his reactions. The toy will hold his attention for a long time, though it may fall off at times. Stay nearby and put the toy back in place.
2. Put some colourful socks on your baby’s feet or use foot rattles if you want. Place a small rolled-up towel or napkin under his hips to elevate his position a bit so he can see his feet easily.
3. Reading to your baby is a proven way of developing their cognitive skills. Get books that are sturdy and contain lots of pictures and images. Your baby will want to touch, feel and even taste the books, so allow him to touch the pages and characters.
4. When your little one is awake, he will be moving his hands and legs continuously. Give him an additional workout by lifting him while lying on your back. Provide toys that surround him so he can pivot himself in different directions.
5. Balls are objects of fascination for most babies as they roll around and wonder how that happens. Bounce the ball, roll it around and gently bounce it against the wall to help your baby understand what a ball can do.

4-Month-Old Baby Care

Your baby is four months old now and will begin kicking around, so it’s time to look at a few safety factors. Baby-proof the immediate vicinity by removing any objects that could topple over and ensuring the place is well-sanitised, too. Dust and grime are everywhere, so make sure you regularly clean and wipe your baby’s bed and toys he handles. If a sleeping pattern is being developed, do not rock or feed your baby to put him to sleep. Let him learn to relax and fall to sleep on his own.

Feeding a 4-Month-Old Baby

By the time your baby is four months old, the feeding process will have developed into an efficient one. Your baby’s feeding skills will have improved as his sucking and latching will be assured and deliberate now. Any difficulties related to feeding will be settled by now. Your infant’s development and nutritional needs will be provided through your breast milk or bottle milk when he is four months old. You can introduce solids at around 6 months when his gut is stronger, and the risk of allergies is lower, too (5).

Sleep of a 4-Month-Old Infant

Your baby’s sleeping pattern will be more defined as he sleeps for shorter periods during the day and for longer and continuous periods during the night. You may think that if he sleeps less during the day, his night sleep will be for prolonged periods. However, day sleep influences nighttime sleep and will help your baby to develop a better sleep routine, too. At this stage, your baby may protest when you try to settle him down for sleep, and this will be a new thing for you. Do not give in to it and keep doing all that you have been doing to get it to sleep. Involve your partner and get his help in putting the baby to sleep (5).

Tips for Parents

Here are a few baby care tips for 4-month-olds for parents that will help to enhance the experience of nurturing a four-month-old baby:

• Place your baby in your lap and put the book you want to read out in front of you. A bright-coloured book is your best bet to keep your eager beaver interested, as it attracts and helps in cultivating his sense of vision, too.
• Give a name or identity to every toy, object and person that your child sees. When his dad arrives, say “Say hi to Daddy” or introduce him to a toy, saying “Here is the ball”. This is a wonderful way of teaching him the name-object association and new words.
• Speak as much as possible to your bundle of joy. In this manner, he will pick up a few words, though he may not understand them. Simple words like dada, mama or baba are easy to repeat for the baby if you repeat them in your daily conversation with him.
• Encourage your little one to remain on his tummy and let him reach out to toys and other objects of interest during this time. This allows him to exercise and develop muscles around the neck and back. Place toys in his field of vision so he can track them by moving his neck and head.
• In order to help your baby have better control over his movements, carry out activities that allow free movement of his arms and elbow joints. Hold his hands while reciting a poem or singing a song and sway them from one end to another. You can also do this by holding a toy and letting him grab the other end.

FAQs

1. Is it common for a 4-month-old to suddenly become more fussy or resistant to people they don’t recognise?

Yes, this is a very common and expected sign of growing cognitive awareness. Around this age, babies are becoming much better at recognising familiar faces and distinguishing them from unfamiliar ones. This newfound ability can lead to stranger anxiety or wariness, which often manifests as fussing, crying, or turning away when someone new approaches or tries to hold them. It’s not a sign that something is wrong; rather, it shows your baby is forming healthy attachments and understands you are their primary source of comfort and safety.

2. How do I know if my baby is ready to drop a nap, and how should I adjust their schedule safely?

Signs that your baby might be ready to transition from four naps to three include consistently fighting one of their naps for over a week, taking very long naps for the others, or suddenly having difficulty falling asleep at their usual bedtime because they aren’t tired enough. The adjustment should be gradual. To safely manage the transition, you can slowly push the morning naps a little later and consolidate awake times, ensuring your baby doesn’t become overtired. The goal is to gently stretch the time between sleeps until one of the nap periods naturally disappears, often the late afternoon catnap, while moving bedtime slightly earlier to compensate.

This was all about taking care of a 4-month-old baby. Every baby is unique and has a different body structure and growth. Do not worry if your baby does not meet his milestones at the given time. For example, premature babies need more time to show ideal development. Speak to your doctor and understand the limitations you should consider while looking at your four-month-old babies development pattern.

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Sources References

1. Nemours Kids Health – Your Baby’s Growth: 4 Months

2. Pregnancy, Birth & Baby – Your baby’s growth and development – 4 months old

3. CDC – Important Milestones: Your Baby By Four Months

4. Mayo Clinic – Infant development: Milestones from 4 to 6 months

5. UCSF Benioff Children’s Hospital – Your Baby at 4 Months