Your baby at 3 months

This month sits between the CDC's 2-month and 4-month checklists. The 4-month list includes cooing and swinging at toys, so it's a good month for sounds and things to reach for.

There's no CDC checklist for 3 months; the CDC's checklists come at 2 months and 4 months. By 2 months, most babies (75% or more) do things like “Smiles when you talk to or smile at her”. Coming up by 4 months: “Makes sounds like ‘oooo’, ‘aahh’ (cooing)”. Both lists are below, with this month's play, talk and reading ideas.

Checked October 29, 2026.

Already, by 2 months

Social/Emotional Milestones

Calms down when spoken to or picked up
Looks at your face
Seems happy to see you when you walk up to her
Smiles when you talk to or smile at her

Language/Communication Milestones

Makes sounds other than crying
Reacts to loud sounds

Cognitive Milestones (learning, thinking, problem-solving)

Watches you as you move
Looks at a toy for several seconds

Movement/Physical Development Milestones

Holds head up when on tummy
Moves both arms and both legs
Opens hands briefly

From the CDC's “Learn the Signs. Act Early.” checklist, Milestones by 2 months, word for word (CDC page dated May 15, 2026; checked October 29, 2026). These are things most children (75% or more) can do by 2 months. The CDC's page has a photo or video of each one.

Coming up, by 4 months

Social/Emotional Milestones

Smiles on his own to get your attention
Chuckles (not yet a full laugh) when you try to make him laugh
Looks at you, moves, or makes sounds to get or keep your attention

Language/Communication Milestones

Makes sounds like “oooo”, “aahh” (cooing)
Makes sounds back when you talk to him
Turns head towards the sound of your voice

Cognitive Milestones (learning, thinking, problem-solving)

If hungry, opens mouth when he sees breast or bottle
Looks at her hands with interest

Movement/Physical Development Milestones

Holds head steady without support when you are holding him
Holds a toy when you put it in his hand
Uses his arm to swing at toys
Brings hands to mouth
Pushes up onto elbows/forearms when on tummy

From the CDC's “Learn the Signs. Act Early.” checklist, Milestones by 4 months, word for word (CDC page dated May 15, 2026; checked October 29, 2026). These are things most children (75% or more) can do by 4 months. The CDC's page has a photo or video of each one.

Play today

Coo back
When your baby says "ooo" or "aah", say it back with a big smile, then wait for their turn.
Swat the toy
Hold a soft toy where your baby can swing an arm at it. Cheer when they touch it, and hold it a little to the other side next time.
Hands together
Gently bring your baby's hands together in front of their face and play with their fingers: "One, two, three, four, five."

Things to say

“Ooo! You said ooo!”
“Your hands! Look at your hands.”
“Here comes the toy. Bop!”

Say it, then wait. Give your baby time to answer with a look, a sound or a word, and answer back.

A rhyme to share

Row, Row, Row Your Boat. Hold your baby close and rock gently to the beat.

The words are on Peabody's Nursery rhymes with lyrics list.

Questions parents ask about this age

When do babies smile?By 2 months: Smiles when you talk to or smile at her
When do babies laugh?By 4 months: Chuckles (not yet a full laugh) when you try to make him laugh
When do babies hold their head up?By 2 months: Holds head up when on tummy
When do babies coo?By 4 months: Makes sounds like “oooo”, “aahh” (cooing)
When do babies recognize their parents?By 2 months: Seems happy to see you when you walk up to her

Talk to your pediatrician if…

Your baby isn't doing the things on the CDC's 2-month list, has lost a skill they once had, or you're worried for any reason. Things on the 4-month list are still coming.

You know your child best. Don't wait. If your child is not meeting one or more milestones, has lost skills he or she once had, or you have other concerns, act early. Talk with your child's doctor, share your concerns, and ask about developmental screening.
CDC, Learn the Signs. Act Early.

If you or the doctor are still concerned, the CDC says to ask for a referral to a specialist, and to call your state's early intervention program (find the number on the CDC's list). You do not need to wait for a doctor's referral or a medical diagnosis to make this call. If your child is younger than 3 years old, contact your local early intervention system.

More from the CDC: Concerned about your child's development? If your child seems unwell, call your pediatrician, or 911 in an emergency.

What the CDC suggests you share with the doctor

What are some things you and your baby do together?
What are some things your baby likes to do?
Is there anything your baby does or does not do that concerns you?
Has your baby lost any skills he/she once had?
Does your baby have any special healthcare needs or was he/she born prematurely?

From the CDC's Milestones by 4 months page. The CDC suggests filling in a milestone checklist and sharing it with your child's doctor; its Milestone Tracker app is free.

Peabody Parents