Baby Development Month by Month
What to expect at every age from 1 month on: development and milestones, sleep totals and wake windows, feeding, crying and soothing, and when to talk to your pediatrician.
How old is your child?
Your 1-Month-Old: Development, Sleep and Feeding
Most newborns sleep 14 to 17 hours across a full day, in short stretches.
Your 2-Month-Old: Development, Sleep and Feeding
The social smile arrives for many babies around 6 to 8 weeks.
Your 3-Month-Old: Development, Sleep and Feeding
Hands become fascinating: batting, grabbing and mouthing everything within reach.
Your 4-Month-Old: Rolling, Laughing and Hands That Finally Meet
Hands find each other at the midline, which is the start of two-handed play.
Your 5-Month-Old: Mouthing Everything, Sounds Copied Back
The mouth is now an investigating tool, not just a feeding one.
Your 6-Month-Old: Rolling Tummy to Back, Passing Things Hand to Hand
Rolling from tummy to back is the CDC's milestone for this month; back to tummy usually comes later.
Your 7-Month-Old: Cause and Effect, and the Run-Up to Crawling
Cause and effect clicks: push this, that happens, do it again.
Your 8-Month-Old: Their Name, the First Crawl, and Pulling Up
Your baby responds to their own name, reliably rather than by chance.
Your 9-Month-Old: Clapping, Waving, and Finding What Is Hidden
Clapping and waving are social gestures, learned by copying and repeated for the response.
Your 10-Month-Old: Cruising the Furniture, Understanding What You Say
Cruising, walking sideways while holding furniture, is the usual route to walking.
Your 11-Month-Old: Pointing, First Words, and Trying to Walk
Pointing is a milestone worth noticing: it means sharing attention, not just wanting.
Your 12-Month-Old: First Steps, and Using Things the Way They Are Meant
Using a brush on hair or a cup to drink shows your baby has learned what things are for.
Your 13-Month-Old: Walking, Carrying, and Following Simple Instructions
Walking looks steadier, with fewer wide-armed wobbles.
Your 14-Month-Old: Imitating, Pointing, and the First Running Steps
Household actions get copied, often within minutes of being seen.
Your 15-Month-Old: Books on Repeat and the First Word Pairs
Your toddler brings you a book and climbs in to hear it.
Your 16-Month-Old: Grouping, Climbing, and Naming What They See
Toys get gathered into rough groups: cars here, animals there.
Your 17-Month-Old: Balls, Puzzles, Spoons, and Big Feelings
Throwing comes long before catching, and aim is not the point yet.
Your 18-Month-Old: Where Two-Step Instructions Start to Land
Objects are carried from room to room as the whole point of the game.
Your 19-Month-Old: Jumping, Pretending, and First Short Sentences
Jumping is attempted well before both feet actually leave the floor.
Your 20-Month-Old: Arranging, Asking, Singing, and Standing Steady
Rows of objects get arranged, inspected, and rearranged with intent.
Your 21-Month-Old: When a Story Comes Back to You
Familiar stories are followed, and a wrong ending gets objected to.
Your 22-Month-Old: Shapes, Dressing, and Solving Small Problems
A circle is told apart from a square before either is named.
Your 23-Month-Old: Feelings, Rules, Stairs, and Sorting Things Out
Feelings get directed at you deliberately, not simply displayed.
Your 24-Month-Old: When Play Starts Running Without You
A crayon makes deliberate lines rather than whole-arm scribble.
Your 25-Month-Old: Three-Word Sentences, Counting, Colors, and Jumping
Three-word sentences carry detail the shorter ones could not.
Your 26-Month-Old: Recounting the Day, Shapes, and Taking Turns
Real events get recounted, with the best part told first.
Your 27-Month-Old: Because and Why Enter the Conversation
Sentences join up with words like because, but and so.
Your 28-Month-Old: Counting by Touch, Hopping, and Invented Tales
A finger touches each object as the number is said.
Your 29-Month-Old: Balance, Detailed Drawings, and Longer Games
Narrow lines and kerbs get walked along on purpose.
Your 30-Month-Old: When Help Is No Longer Welcome
Your child insists on dressing alone and refuses your help.
Your 31-Month-Old: Longer Sentences, Rules Understood, Feelings Named
Sentences run longer, with several ideas held in one breath.
Your 32-Month-Old: Solo Play, Shared Stories, and Cause and Effect
Solo play holds together without you being in the room.
Your 33-Month-Old: Play That Needs Somebody Else
Other children become collaborators rather than scenery.
Your 34-Month-Old: Sticking to Rules and Explaining Feelings
A rule survives a whole game rather than the first two turns.
Your 35-Month-Old: Retelling, Multi-Step Tasks, and Playing Together
A known story is retold with beginning, middle and end intact.
Your 36-Month-Old: Three Years Old, Learning on Their Own
Stories run to several linked parts and keep their characters straight.
New months are added regularly; each page is reviewed against AAP, CDC and WHO guidance before publishing.