Child Development Timeline

A baby and a mother playing ball. — The first year of life is full of wonder and growth. Sam Edwards / Getty Images

The following guideline describes the various physical, cognitive, emotional, and social developmental changes and milestones to be expected during the first year of life.

It is of utmost importance to remember that the timeline is approximate, not absolute. Each child develops at his or her own pace, and some stages may occur earlier or later.

Birth to 1 Month Developmental Milestones

There is significant growth during the first month of life. At this time, reflexive movements dominate, and infants have little, if any purposeful physical activity.

Growth

Weight decreases by 10% immediately after birth and returns to birth weight by 2 weeks of age
Gains 1 oz/day; 2 lbs/month
Length increases 3.5 cm/ month

Movement and Activity

Head droops without support
Limbs flexed
Purposeless movement
Grasps objects placed in hands
Sucks objects placed in mouth
Sleeps about 16 hours/day

Sensory

Nearsighted; can see objects clearly 8-12 inches from face
Fixated gaze; cannot follow objects (like a doll's eyes)

Social

Hearing is preferential to the female voice
Easily startled

1 to 2 Month Developmental Milestones

Growth

20g/day (1.5 lbs/month) weight gain
2 cm/month length increase

Movement and Activity

More deliberate movements
Limbs more extended
Can lift head temporarily when lying on stomach
Some delay in raising head when pulled to a sitting position from lying on back
Hands tightly fisted most of the time

Sensory

Follows moving object with eyes

Social

Smiles involuntarily
Responds to sounds

Communication

Throaty noises, gurgles

2 to 3 Month Developmental Milestones

2 MONTHS OLD

Growth

Growth rate is still significant, but not as rapid as in the first 2 months
Posterior fontanelle ("soft spot") closes

Movement and Activity

Lifts head (45°) for a sustained time when lying on stomach
Continued lag on raising head when pulled to sitting position from lying on back
Hands fisted half of the time
Will follow objects, consciously turn head 180°

Social

Smiles voluntarily ("social smile") in response to appropriate stimuli (familiar faces or voices)
Recognizes facial expressions

Communication

Cries approximately 3 hours/day
Coos, makes single-syllable sounds

3 MONTHS OLD

Growth

Gains 1¼ lbs/month
Length inc. 2 cm/month

Movement and Activity

Minimal delay on raising head when pulled to sitting position from lying on back (bobbing)
Will reach for objects but misses while lying on back; waves at objects
Lifts head and chest when lying on stomach; rests on arms
Rolls side-to-side
Hands mostly unfisted
Small circular limb movements
Sleeping approximately 14 hours/day, with 9-10 occurring at night

Sensory

Explores own body

Cognitive

Will look at area where an object used to be (no sense of object permanency)

Social/Emotional

Increased eye contact
Listens to music
Appropriate facial expressions in response to emotions (anger, fear, joy)
Mimics others' facial expressions
Increased awareness/interest in surroundings
Distracted during nursing
Shows different emotions (anger, fear, joy)

Communication

Varied types of crying
Says "ahh"

4 to 5 Month Developmental Milestones

4 MONTHS OLD

Growth

Gains 1 lb/month

Movement and Activity

No head lag when pulled to sitting position from lying on back
Reaches and grasps objects, brings to them to mouth while lying on back
Holds objects indefinitely
Stands when held
Plays with hands and feet

Social/Emotional

Shows displeasure at withdrawal of social contact
Excited at the sight of food

Communication

Remains silent while others speak, then vocalizes

5 MONTHS OLD

Movement and Activity

Transfers object from hand to mouth to opposite hand
Begins to teethe

Social/Emotional

Plays with mirror image

Communication

Imitates speaker
Sing-song quality to voice
Makes raspberry sound

6 to 8 Month Developmental Milestones

6 MONTHS OLD

Growth

1 lb/month
1.5 cm/month
Lower central incisors erupt

Movement and Activity

Drinks from a cup with help
Holds own bottle
Moves objects hand-to-hand directly
Rolls over
Sits briefly, leans forward, supports self with arms

Social/Emotional

Discriminates between parents and strangers ("stranger anxiety")
Copies facial expressions

Communication

Babbles

7 MONTHS OLD

Growth

Upper central incisors erupt
Lower lateral incisors erupt

Movement and Activity

Sits unsupported, pivots while sitting
Pivots and crawls while lying on stomach
Lifts head indefinitely while lying on back
May stand, bounce
Reaches out, grasps object with palm
Bangs, shakes objects
Puts feet in mouth

Social/Emotional

Prefers mother
Anxious when away from mother (Separation Anxiety)
Pats mirror image

Communication

Responds to changes in social contact/context

8 MONTHS OLD

Growth

Upper lateral incisors erupt

Movement and Activity

Crawls easily on stomach
Pulls self to stand using furniture
Feeds self with hands
Will take 2 objects and hold 1 in each hand

Sensory

Vision close to fully-developed

Cognitive

Begins to understand objects' uses (drink from a cup, brush hair with a brush)
Realizes size differences between objects

Social/Emotional

Performs "tricks"
No longer automatically accepts feedings, will turn spoon away

Communication

Multisyllabic babbling

9 to 10 Month Developmental Milestones

9 MONTHS OLD

Growth

Gains 12g/day, 13oz/month
Length inc. 1.2 cm/month

Movement and Activity

Grasps object between thumb and forefinger ("pincer grasp")

Cognitive

Will search for an object when it is taken away, understands that it exists even though it can no longer be seen ("object constancy")

Communication

Single syllable "words" ("ma", "da")
Understands "no"
Inflection with babbling

10 MONTHS OLD

Growth

First molars erupt

Movement and Activity

Sits up alone and indefinitely
Crawls on hands and knees
Crawls up stairs
Walks while holding on to furniture (cruising)
Walks with two hands held

Cognitive

Understands simple phrases
Follows simple directions
Associates "mama" with mother and "dada" with father
Can find objects by name when asked

Social/Emotional

Waves
Plays "peek-a-boo"
Tests autonomy (crawls away from mother and checks for her reaction)

Communication

First "real" words ("mama", "baba")
Conversational babbling

11 to 12 Month Developmental Milestones

11 MONTHS OLD

Movement and Activity

Stands alone and unsupported
Walks with one hand held
Drink from cup without help

Social/Emotional

Plays alongside others, but not with others (parallel play)

Communication

Uses words meaningfully

12 MONTHS OLD

Growth

Weight has tripled since birth
Length has doubled since birth

Movement and Activity

First steps
Feeds self with a spoon
Transfer object from self to other with pincer
Attempts to stack two blocks
Helps with dressing by adjusting posture

Social/Emotional

Identifies self in mirror
Attempts simple conversations