Your baby is going to be growing fast the first year.  Everyone comments about how a newborn is so tiny.  Then the next time they see them, they comment on how they cannot believe how much they have grown.  In reality the baby actually is growing quite a bit every day.  Some babies will initially lose some weight the first few days after delivery, but after than rapid growth is expected.  It is not unusual for a baby to lose 5-10% of their weight in the first 5-7 days.  However, after 10-14 days they will be back to original birth weight.

In my first article of this series I discussed the social development of trust and what a parent can do to develop that trust.  You should really go and read it.  This article is focusing on the physical development of the infant.  While it is true that Nature will do its thing, the parent or caregiver has a lot of influence over how the growth of the baby occurs.  The nutrients that are supplied, the opportunity they are given to sleep and the physical environment all have influences on the physical development of the baby. 

This article will tell about the things a parent should be looking for and what they can do to ensure the physical growth of the child is able to be optimized.  The growth of the baby is so rapid I have had to break it down into subgroups to be able to explain this well.  Remember not all babies are the same and some rapid growth or delayed growth may be normal.  However, if you are concerned you should contact your pediatrician or developmental specialist.  This article should in no way be a substitute for the valuable information they can give you.  You and they know your child better than I do sitting from behind a computer and many miles away. 

By Four Months

 4 month old babyCredit:

By four months old, typically a baby will weigh somewhere around 15 pounds, give or take 3 pounds.  They will be about two feet tall, given a couple of inches. Proper feeding will ensure they physical milestones are met.  However, there are many factors which play a part in this development, genetics being one.  If the parents are shorter, the children may be shorter.  That is just how it works.

One of the most common complaints about babies is they do not sleep throughout the night.  Parents have to wake up and comfort the baby.  By four months old the baby should be sleeping about 6 hours during the night.  They are getting into a schedule.  Babies typically will sleep somewhere between 14-17 hours during a 24 hour period.

Babies are born legally blind.  However, by four months old they should have developed enough muscles in the eyes to be able to be fixed on a non moving object but also be able to follow a person or object.  Babies will turn their head to follow their parent of someone walking by. 

By four months the baby should be grasping small items.  They will lose the reflex they had to gripe things as a newborn and this will be replace by a conscious effort to grasp things such as the parents’ fingers or rattlers.  They may still be too small to hold a bottle, but with some support they can almost do this.

The trunk muscles are getting stronger (gross motor skills) and bones are starting to solidify.  Therefore, by four months the baby is able to kick and flap their arms, hands, feet, and legs.  This happens especially when they get excited.  The baby will also learn to roll over from their stomach to their back.  The reverse may still be too much of an obstacle for them.  Baby should also be able to sit up with support by this time.  Pillows propping them up or the parents holding them should suffice.

Physical Development at 8 Months

By 8 months of age, baby will weight somewhere between 14-23 pounds and will be up to 30 inches long. 8 month old babyCredit:

During this time the first tooth will appear.  This can be a blessing and problem for parents.  They are excited about the teeth, but find that the baby can bite them and chew on things now and that is a concern.  As a result of or a cause of the tooth appear, the baby will start to drool quite a bit.  They will chew on things and will carry things to their mouth.  Parents become alarmed by this.  Remember, taste is one of the 5 senses and if the parent does not allow this sense to be utilized, optimal learning is not taking place.  This should be monitored though. 

The baby should have a well established sleeping pattern to be able to sleep throughout the night.  However, they will still awaken some times.  They should be sleeping about 12-14 hours total during a 24 hour period.  They will still want to take 2-3 naps during the day.  Usually these will last 1-2 hours. 

The fine motor skills are getting better and the baby might reach for things such as a cup of spoon when they are eating.  Encourage this but understand a mess will probably be made.  The fine motor skills are still not tuned yet. They will start to be able to eat some chopped foods and some other solid foods.  Be careful on what you feed them and be aware of possible food allergies. They can pick up things with their finger and thumb.  It may go straight to their mouths.  They are able to transfer objects from one hand to another. 

The gross motor skills are getting a lot better. They can now roll from front to back and vice versa.  They can sit up on their own without support.  The baby will be able to get up on their hands and knees and rock back and forth.  They may not be able to move forward yet, but do not be surprised if they do. 

The hair on their heads is growing faster and should be covering most of the head.  One thing I found interesting is that the eye color is established by this time.  They may have been born with one color of eyes and then changes.  Hair color does change as well.  I found pictures of me as a baby with dark hair.  I have had blonde hair as long as I can remember.  The joke in my family is my mom switched me when I was younger with my cousin, who had light colored hair and now has dark hair.

By 12 Months

12 month old babyCredit:

By the first birth day your baby will weigh between 18-28 pounds and will be between 28-32 inches long.  Baby will sleep about 11-13 hours a night and should sleep throughout the night.  They will still take naps but usually only 1-2 in the afternoon.  They will only be for about 1 hour now.  Less time for other work for the parent or caregiver.

Babies will either start to wean themselves from the bottle or breast or can be weaned easier.  They will need 3 meals a day and a couple of snacks to replace the nutrients they were receiving from the bottle or breast. They will start to be able to drink from a cup on their own and will be able to eat finger foods, such as crackers, cookies, toast, and other things. 

Gross motor skills are getting a lot better.  They will be able to crawl well.  Sometimes very fast.  They can pull themselves up and walk while holding onto something, such as furniture or with help from parents. 

The fine motor skills are developing and with this more things are able to be stuck in the mouth. You can bet about any small object lying in the floor will be given the taste test.  Babies will find the cabinet doors and will really enjoy opening and closing them. 


The rapid physical growth usually excites the parents but can open up a lot of problems with the home environment.  You will have to take precautions about what your child is exposed to, now that they can do more and get around better.  Baby proof your home and keep a watchful eye on them.  Do not just plop them down in front of the television and leave them in the seat for too long.  Let them explore but watch them.  Encourage them to get farther away from you but still within a safe distant that they can return when they want or need to. 

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