A. Two weeks

1. Motor (fine and gross)
   1. Stares at face and tracks 90° horizontally
   2. Turns to voice
   3. Symmetrical movements
2. Social: none
3. Language: none
4. Parenting
   1. Normal Increase in crying which peaks at 6 weeks

B. Two Months

1. Motor
   1. Lifts head in prone
2. Social
   1. Smiles in response to social overtures
3. Language
   1. Listens and responds when speaker quiet
4. Parenting
   1. Impossible to spoil infant by picking up when cries

C. Four Months

1. Motor
   1. Pull to sit with head lag
   2. Holds rattle then lets go
2. Social
   1. Regards stranger with interest or pleasure
3. Cognitive
   1. Stares at one hands
   2. Crumples paper joyfully
4. Language
   1. Recognizes sounds
   2. Excited by parents' voice
5. Parenting
   1. Put to bed while still drowsy
   2. Do not rock to sleep

D. Six Months

1. Motor
   1. Firm grasp of objects
   2. Passes cube from one hand to another
2. Social: as above
3. Cognitive
   1. Looks after a fallen object
4. Language
   1. Babbles
5. Parenting
   1. Routines important
   2. Sleep and separation problems may begin

E. Nine Months

1. Motor
   1. Thumb-finger or pincer grasp
   2. Grabs Crayons efficiently
   3. Sits stablely
2. Social
   1. Plays peek-a-boo
   2. Pat-a-cake
3. Cognitive
   1. Inspects Object, then mouths
   2. Bangs Cubes
4. Language: as above
5. Parenting
   1. Avoid feeding battles
   2. Give child spoon
   3. Continue finger foods

F. Twelve Months

1. Motor
   1. First Steps
2. Social
   1. Consolable
   2. Willing to explore new environments from safety of parents lap
3. Cognitive
   1. Looks for hidden object
   2. Object constancy
4. Language
   1. First words other than mama or dada
   2. Jargoning
5. Parenting: as above

G. Fifteen Months

1. Motor
   1. Walks well
2. Social
   1. Reads parents expressions to see if safe to explore
3. Cognitive
   1. Uses objects correctly in play
4. Language
   1. Follows single-step command without gestures
   2. Speaks at least on word
5. Parenting
   1. Equate discipline with teaching
   2. Give frequent praise
   3. Providing choices reduces power struggles

H. Eighteen Months

1. Motor
   1. Walks up steps
   2. Walks backwards
2. Social: as above
3. Cognitive
   1. Works wind-up toys b. Understands cause and effect such as on-off buttons
4. Language
   1. Six words that are not echolalic
   2. Indicates desired objects with index finger not whole hand
5. Parenting: as above

I. Twenty Four Months

1. Motor
   1. Walks backwards
2. Social
   1. Increase in clingy behavior
3. Cognitive
   1. Understands substitution (in play one object stands for another)
4. Language
   1. Two word phrases
   2. Points to at least one body part
5. Parenting
   1. Pick battles selectively to minimize power struggles
6. Cognitive development is delayed in cocaine-exposed infants [2]

J. Thirty Months

1. Motor
   1. Walks up and down steps independently
   2. Copies
2. Social
   1. Mostly self dresses
   2. Daytime diaper dryness (average age)
3. Cognitive
   1. Combines play actions (able to rock doll and put to bet)
4. Language
   1. Names several body parts
   2. Able to follow tow prepositional commands
5. Parenting: as above

K. Three Years

1. Motor
   1. Jumps with both feet off the floor
   2. Mature crayon grasp
2. Social
   1. Separates from caregivers more easily
   2. Nigh time diaper dryness (average age)
3. Cognitive
   1. Plays out familiar events and changes outcome
4. Language
   1. Three to four word sentence
   2. Gives full name

L. Four Years

1. Motor
   1. Balances on one foot for four to five seconds
2. Social
   1. Understands taking turns
   2. Arbitrates dispute with words not hitting
3. Cognitive
   1. Draws a person with three or more body parts
   2. Role assignments in play
4. Language
   1. Speaks in sentences
   2. Grammar is usually correct
   3. Asks questions

M. Five Years

1. Motor
   1. Balances on one foot for 5-10 seconds
   2. Copies square and triangle shape
2. Social
   1. Plays well in a group of children
   2. Dresses with little help
3. Cognitive
   1. Plays out imaginary scripts
   2. Beginning to understand and question surrounding world
4. Language
   1. Correct use of "I" and "me"
   2. Past tense
   3. Plurals

N. Six Years

1. Motor
   1. Walks backward
   2. Heal to toe walking
   3. Begins sport and dance
   4. Copies diamond shape
2. Social
   1. Understands rule-based games
   2. Has best friend
3. Cognitive
   1. Repeats a four digit string
   2. Counts 5 items
   3. Simple math
4. Language
   1. Fluency
   2. Names 4-5 things to eat or wear in twenty seconds
   3. Knows names of all letters
   4. Recognizes a few words

O. Seven Years

1. Cognitive
   1. Understands same and different concept
   2. Knows left from right
   3. Masters addition
2. Social: as above
3. Cognitive: as above
4. Language
   1. Defines simple adjectives and pronouns
   2. Tells more complex stories
5. Parenting
   1. Increase responsibilities at home
   2. Assign specific chores
   3. Often attach positive outcome to carrying out chores

P. Eight Years

1. Spells most one syllable words
2. Increasingly complex stories
3. Normal puberty (Tanner stage 2 in girls) can begin at 8 (through 13) years old [3]
4. Growth hormone increased height in short normal children (>2 SD below mean height) [4]
   1. No untoward effects on pubertal progression
   2. No changes in cardiac parameters
   3. Increases in insulin and insulin like growth factor 1 (IGF-1) during treatment
   4. Duration of therapy was 6.5 years on average
   5. Short normal children reached mean height levels with treatment

Q. Nine to Ten Years

1. Motor
   1. Plays sports
2. Cognitive
   1. Repeats four digits in reverse
   2. Lists days of the week backwards
   3. Three object recall at 10 minutes
   4. Simple addition, subtraction, multiplication and division calculations
   5. Understands time concept
3. Language
   1. Spells simple two syllable words
4. Puberty for boys (Tanner stage 2, initial pubic hair, penile enlargement) age 9.5-13.5 years [3]

References

1. American Academy of Pediatrics. 1997. Guidelines for Health Supervision. Third Edition
2. Singer LT, Arendt R, Minnes S, et al. 2002. JAMA. 287(15):1952
3. Carel JC and L©ger J. 2008. NEJM. 358(20):2366
4. McCaughey ES, Mulligan J, Voss LD, Betts PR. 1998. Lancet. 351(9107):940