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4 Month Old Baby

At 4 month old baby has increased in physical cognitive and communicative development.

At 4 month old the baby can raise up on her arms when place on his tummy.  In month four, your baby’s personality has probably grown even more pronounced.

Physical Development

How Much Should A 4 Month Old Weigh? In month four, the baby should weight between 11.24 -18.95 pounds.

What should the height of a 4-month-old be?  In month four, the baby should be 22.8 to 26.09 inches.

How much should his head size be? In month four, the baby ‘s head should be 15.03-17.28 inches.

What Should Your Baby Be Doing At 4 Months?

Motor Development

In month four, the baby’s increases alertness and evolving motor skills. Your baby becomes more aware of his surroundings.  

The motor development helps the child gain balanced and bring large muscles under control. The motor development helps the baby to master physical such as sitting, crawling, and grabbing.

Cognitive Development

At 4 months, a baby’s cognitive development is increasing exponentially. Pay attention to your child and how they play, learn speak, and act. When your baby is under four months, she’ll enjoy looking at herself in a mirror.  The baby will be able to display whether he is happy or displeased.

Communicative Development

At 4 months, the baby is busy sorting out the basics of emotions and communications.  During this stage, the baby is developing more ways to interact with you.  

Your baby’s range of sounds and facial expressions continue to grow, and your baby is also imitating sounds, which are the first attempts at speaking.


The Moro Reflex go away completely during the fourth month.  The rooting starts to diminish during the fourth month.

Sensory Development

How clearly can babies see?

A baby’s vision improves dramatically over the first year. The baby will able to see pretty clearly by the time he reaches 12 months old.  The vision is not completely developed until the ages between 3 and 5 years old.

How Well Can A Four Month Old Hear?

 During this stage, a four-month-old is able to recognize his parent’s voice. The baby usually responds back with a smile.

What Sleep Schedule Do Babies Follow?

The baby’s sleeping pattern can be anywhere from seven to nine hours.  He will also be taking several naps through out the days.

Sleep Regression In Babies

The 4 month sleep regression occur when a baby who is normally sleeping well begins to wake frequently at night and or refuses naps.  The baby will go from sleeping through the night, to suddenly waking several times a night.

How Much Should A 4-Month-Old Eat?

At 4 months old, the baby will be fed between four to five feeds a day. Babies who are getting breastfed take more feeds per day usually around six to eight feeds daily.

Should You Start Solids At Four Months?

Many doctors recommend starting your baby on solids between 4 and 6 months.  If the baby starts displaying signs of not being happy with just milk then it might be time to start introducing solid foods.


At 4 months, the third dose of vaccinations are due.  The different vaccines are DTaP, IPV, Hib, Pneumococcal, and Rota.

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