While all babies may grow at a different rate, the following is the average for boys and girls 4 to 6 months of age:
Weight. Average gain of 1 to 1¼ pounds each month; by 4 to 5 months has doubled birth weight
Height. Average growth of ½ to 1 inch each month
Head size. Average growth of about ½ inch each month
This age is very social, and babies start moving in much more purposeful ways. Babies may progress at different rates. But these are some of the common milestones most babies reach in this age group:
Grasp, Moro, root, and tonic neck reflexes (reflexes normally present in young infants) disappear
Balances head well
Leans on hands to support when sitting
Pushes up with straight arms when on tummy
Rolls from tummy to back by 6 months
Starts drooling (not always a sign of teething)
Naps 2 to 3 times a day, for 1 to 3 hours each (on average)
Starts to sleep longer at night (6 to 8 hours consistently)
Has full-color vision, able to see at longer distances
It's very exciting for parents to watch their babies become social beings who can interact with others. Every baby develops speech at their own rate. But these are some of the common milestones most babies reach in this age group:
Takes turns making sounds with you
Blows bubbles or "raspberries"
A baby's awareness of people and surroundings increases during this time, and they may start to interact with people other than their parents. Babies may progress at different rates. But these are some of the common milestones most babies reach in this age group:
Knows familiar things and people
Puts things in their mouth to explore them
Reaches to grab a toy they want
Closes lips when they don't want more food
Likes to look at self in a mirror
Here are some ways to foster your baby's emotional security:
Repeat sounds and smile when your baby makes sounds.
Laugh with your baby.
Talk to and imitate your baby during feeding, dressing, changing diapers, and bath time.
Spend time on the floor playing with your child every day.
Dance with your baby and do other rhythmic movements.
Introduce your baby to other children and parents.
Place safe toys near your baby to encourage reaching and grasping.
Encourage laughing and play by making funny faces or sounds or blowing on baby's belly and laughing.
Play peek-a-boo games to help develop object permanence, the understanding that objects are still present even though they can't be seen.
Show your baby bright picture books and interesting objects.
Show your baby their reflection in a mirror.
Read books and stories to your baby, and point out pictures.
Take your baby outside to see new things and people.
Hold your baby for feedings and cuddle when they are awake.
Hold and comfort your baby when they are unhappy.