Pediatric Milestones | Quick Guide

2 Months

Social / Emotional

Smiles at people (social smile)
Can be calmed by caregiver
Looks at face

Language

Coos, makes sounds
Turns head toward sounds
Different cries for different needs

Cognitive

Pays attention to faces
Follows things with eyes
Acts bored if activity doesn't change

Motor

Holds head up during tummy time
Makes smooth movements with limbs
Pushes down on legs when feet are flat

4 Months

Social / Emotional

Smiles spontaneously
Likes to play with people
Copies movements and facial expressions

Language

Babbles; uses consonants (ba, da)
Cries differently for different needs
Responds to sound with sound

Cognitive

Reaches for objects with one hand
Uses hands and eyes together
Watches a face closely

Motor

Holds head steady, unsupported
Pushes up on elbows (tummy time)
May roll from tummy to back
Brings hands to mouth

6 Months

Social / Emotional

Knows familiar faces; stranger anxiety begins
Likes to play with others
Responds to emotions in others

Language

Responds to own name
Strings vowels together (ah, eh, oh)
Makes sounds to show joy/displeasure

Cognitive

Looks at things nearby
Brings things to mouth
Shows curiosity; tries to get things out of reach

Motor

Rolls both ways (front to back, back to front)
Sits with support
Supports weight on legs when standing

9 Months

Social / Emotional

Stranger / separation anxiety
Has favorite toys and people
Understands "no"

Language

Babbles using mama/dada (nonspecific)
Copies sounds and gestures
Points at things

Cognitive

Object permanence begins
Looks for hidden objects
Plays peek-a-boo

Motor

Sits without support
Crawls (may vary in pattern)
Pulls to stand
Pincer grasp developing

12 Months

Social / Emotional

Shy or anxious with strangers
Cries when parent leaves
Prefers certain people
Repeats actions that get attention

Language

Mama/dada with meaning (specific)
Says at least 1 word besides mama/dada
Waves bye-bye
Understands simple instructions

Cognitive

Explores by banging, shaking, throwing
Finds hidden objects easily
Follows simple directions
Copies gestures

Motor

Stands momentarily without support
May take a few steps alone
Pincer grasp established
Drinks from a cup

18 Months

Social / Emotional

Plays alone near others (parallel play)
Points to show interest
Aware of others' emotions

Language

Speaks at least 10 words
Shakes head "no"
Points to ask for help
Identifies 1 body part

Cognitive

Knows what ordinary objects are for
Scribbles on own
Stacks 2–4 blocks

Motor

Walks independently
Climbs onto and off furniture
Feeds self with spoon
Helps undress self

2 Years (24 Months)

Social / Emotional

Copies others, especially older children
Excited around other children
Defiant behavior emerging

Language

Speaks at least 50 words
2-word phrases (more milk, go bye-bye)
50% intelligible to strangers
Follows 2-step instructions

Cognitive

Finds hidden objects with 2 steps
Sorts shapes and colors
Completes sentences in familiar books
Builds tower of 4+ blocks

Motor

Runs; kicks a ball
Walks up and down stairs with support
Turns over a container to pour out contents
Begins to run

No two-word phrases by 24 months: refer for speech-language evaluation. Screen for autism spectrum disorder at 18 and 24 months using M-CHAT-R/F.

3 Years

Social / Emotional

Copies adults and friends
Shows affection for friends
Understands "mine" and "his/hers"
Shows wide range of emotions

Language

2–3 word sentences
75% intelligible to strangers
Follows 2–3 step instructions
Knows name, age, gender

Cognitive

Works toys with buttons and levers
Plays make-believe
Completes 3–4 piece puzzles
Understands "same" vs. "different"

Motor

Climbs well
Rides tricycle
Walks up/down stairs alternating feet
Draws a circle

4 Years

Social / Emotional

Enjoys playing with other children
Cooperative play
Negotiates solutions to conflicts
Understands rules of simple games

Language

Tells stories
Sings songs/rhymes from memory
100% intelligible to strangers
Knows first and last name

Cognitive

Understands counting
Draws a person with 2–4 body parts
Recognizes some letters and numbers
Understands time concepts (today, later)

Motor

Hops on one foot
Catches a ball most of the time
Uses scissors
Draws circle and square

5 Years

Social / Emotional

Wants to please friends
Aware of gender
Distinguishes fantasy from reality

Language

Speaks in complete sentences
Tells a simple story with beginning/end
Uses future tense
Prints some letters; recognizes rhymes

Cognitive

Counts to 10+
Draws a person with 6+ body parts
Copies triangle and other shapes
Knows about everyday things (money, food)

Motor

Stands on one foot for 10+ seconds
Hops, skips, somersaults
Uses fork, spoon, sometimes knife
Writes some letters; draws recognizable person

Red Flags for Developmental Delay

Language Red Flags

No babbling by 12 months
No single words by 16 months
No 2-word phrases by 24 months
Loss of previously acquired language at any age
Not using gestures (pointing, waving) by 12 months

Motor Red Flags

Not sitting by 9 months
Not standing by 12 months
Not walking by 18 months
Persistent toe walking after 2 years
Loss of previously acquired motor skills

Social / ASD Flags

No social smile by 6 months
No eye contact or pointing by 12 months
No imaginative play by 18 months
Not interested in other children
Repetitive behaviors, restricted interests

Cognitive / Global Delay

Delay across multiple domains
Regression at any age is always concerning
Failure to follow simple commands by 18 months
Not copying simple actions by 12 months

Regression at any age (loss of previously acquired skills) always warrants urgent evaluation. Screen all children for autism at 18 and 24 months with M-CHAT-R/F.

Developmental Screening Tools

M-CHAT-R/F (Modified Checklist for Autism in Toddlers): used at 18 and 24 months
ASQ-3 (Ages and Stages Questionnaire): broad screen at 9, 18, 30 months; parent-completed
Denver Developmental Screening Test II: covers 0–6 years, 4 domains
PEDS (Parents' Evaluation of Developmental Status): any age, parent-reported
Bright Futures (AAP): recommends formal developmental surveillance at every well-child visit

Screen 9 mo Screen 18 mo Screen 24–30 mo M-CHAT-R at 18 and 24 mo

Primitive Reflexes

Normal Reflexes and Expected Disappearance

Moro reflex: disappears by 4–6 months
Rooting / sucking: disappears by 4–6 months
Palmar grasp: disappears by 5–6 months
Asymmetric tonic neck (fencing): disappears by 6 months
Plantar grasp: disappears by 9–12 months
Parachute reflex: appears by 9 months, persists

Clinical Significance

Persistence beyond expected age suggests CNS abnormality
Absent Moro in newborn: rule out brachial plexus injury or clavicle fracture
Asymmetric reflex: consider hemiparesis
Loss of parachute: concerning for regression

Key Clinical Pearls

Developmental delay: performance significantly below average in one or more domains for age
Premature infants: use corrected age until 24 months for milestone assessment
Language milestones are among the most sensitive indicators of global development
Social smile by 6 weeks is reassuring; absent by 3 months is concerning
Object permanence begins around 8–9 months (basis for peek-a-boo)
Stranger anxiety peaks at 9–12 months; expected and normal
Parallel play is normal at 18 months–3 years; cooperative play develops after 3 years
Hearing loss is the most common missed cause of language delay — always screen