Growth & Development: Erikson, Piaget, and Milestones by Age (Pediatrics)

Prepared for Pass the Shift (owner: Kristina, RN). Always follow your facility’s protocols, provider orders, and current references.

1. Overview: Principles of Development

Cephalocaudal (head to toe): head control comes before sitting, then walking
Proximodistal (center outward): arm control before finger control
General to specific: whole-hand grasp before pincer grasp
Development is sequential but individual — the order is predictable, the timing varies. “Most children do this by” ages (CDC milestones) are not the average; a missed milestone or loss of skills deserves follow-up
For preterm infants, use corrected (adjusted) age until about age 2 (chronologic age minus weeks born early)

AAP recommends standardized developmental screening at 9, 18, and 30 months and autism screening at 18 and 24 months, plus surveillance at every well visit.

2. Physical Growth Rules of Thumb

Measure	Rule
Weight	Doubles by ~5–6 months, triples by 12 months, quadruples by ~2–2.5 years
Length	Increases ~50% by 12 months; birth length roughly doubles by age ~4
Head circumference	Measured routinely to age 2–3; fast growth in the first year
Fontanelles	Posterior closes by ~2–3 months; anterior by ~12–18 months
Teeth	First tooth ~6 months; ~20 primary teeth by ~2.5–3 years
Growth charts	WHO charts birth–2 years; CDC charts 2–20 years; BMI-for-age after age 2

3. Theorists at a Glance

Age	(psychosocial)	(cognitive)	Freud (psychosexual)
Infant (0–1 yr)	Trust vs. mistrust — consistent, loving care	Sensorimotor (0–2): learns through senses; ~8–9 mo	Oral
Toddler (1–3)	Autonomy vs. shame & doubt — “me do it,” choices	Sensorimotor → preoperational	Anal (toilet training)
Preschool (3–6)	Initiative vs. guilt — make-believe, starting projects	Preoperational (2–7): , magical thinking, animism, no conservation	Phallic
School-age (6–12)	Industry vs. inferiority — skills, achievement, rules	Concrete operational (7–11): logic about concrete things, conservation, classification	Latency
Adolescent (12–18)	Identity vs. role confusion — peers, body image, who am I	Formal operational (11+): abstract and hypothetical thinking	Genital

4. Milestones by Age (key NCLEX examples)

Age	Gross motor	Fine motor	Language / social
2 mo	Lifts head when on tummy	Opens hands briefly	Social smile, coos
4 mo	Holds head steady unsupported; may roll front-to-back	Brings hands to mouth, holds toy	Laughs, babbles
6 mo	Rolls both ways; sits with support → briefly alone	Transfers objects hand to hand; rakes	Knows familiar faces; stranger anxiety begins ~6–8 mo
9 mo	Sits without support, crawls, pulls to stand	Crude → developing pincer grasp; bangs objects	Separation anxiety, “mama/baba” babble, object permanence
12 mo	Cruises, may take first steps	Neat pincer grasp; drinks from cup with help	1–3 words, waves bye-bye
15–18 mo	Walks alone (by ~18 mo at the latest), climbs stairs with help	Scribbles, stacks 2–4 blocks, uses spoon	~10–20 words by 18 mo; points to show interest
2 yr	Runs, kicks ball, walks up stairs	Stacks ~6 blocks, turns pages	2-word phrases, ~50+ words; parallel play; negativism (“No!”), tantrums
3 yr	Pedals tricycle, jumps	Copies a circle; uses a fork	3-word sentences; mostly understood by strangers; begins to share
4 yr	Hops on one foot	Copies a cross / square; uses scissors	Tells stories; associative play; imaginary friends
5 yr	Skips, may ride a bike with training wheels	Copies a triangle; prints some letters; ties shoes (~5–6)	Cooperative play, follows rules

Red flags (refer): no social smile by ~2–3 months, not sitting by 9 months, not walking by 18 months, no words by 16–18 months, no 2-word phrases by 24 months, any loss of language or social skills at any age, persistent primitive reflexes, lack of eye contact or pointing.

Primitive reflexes: rooting/sucking (disappear ~4 mo), Moro (~4–6 mo), palmar grasp (~4–6 mo), tonic neck (~4–6 mo), plantar grasp (~9–12 mo), Babinski (~12–24 mo).

5. Play, Toys, and Safety by Age

Age	Type of play	Good toys	Safety focus
Infant	Solitary, sensory	Mobiles, rattles, soft books, mirrors, textured toys	Safe sleep, falls, choking, car seat rear-facing, burns
Toddler	Parallel (side by side)	Push-pull toys, blocks, large crayons, shape sorters	Poisoning, drowning, choking, falls, burns
Preschool	Associative, imaginative	Dress-up, puppets, tricycle with helmet, simple puzzles	Street and water safety, stranger safety, booster seats
School-age	Cooperative, rules, collections	Board games, sports, crafts, models	Bike helmets, sports injuries, firearms safety
Adolescent	Peer group activities	Music, sports, video games, phones	Motor vehicle crashes, substance use, firearms, suicide risk, risky sexual behavior, online safety

6. Hospitalization Responses and Nursing Approaches

Age	Biggest fear / stressor	Nursing approach
Infant (> 6 mo)	Stranger and separation anxiety	Keep parent present, consistent caregivers, comfort objects
Toddler	Separation anxiety (protest → despair → detachment), loss of control, regression	Rooming-in, routines, simple choices (“Which cup?”), let them handle equipment, expect regression (e.g., toileting) — don’t scold
Preschool	Bodily injury/mutilation, fear of the dark, magical thinking (illness as punishment)	Bandages reassure them; explain right before procedures in simple words; therapeutic play with dolls; reassure they did nothing wrong
School-age	Loss of control, injury, falling behind school/peers	Explain with diagrams/models; let them help; schoolwork; privacy beginning
Adolescent	Body image changes, loss of independence, separation from peers	Privacy, confidentiality (within legal limits), include in decisions, peer contact

Procedure prep: toddlers — immediately before; preschool — shortly before (minutes to an hour); school-age — earlier with detail; adolescents — in advance, as adults would. Treatment room for painful procedures; the bed is a “safe place.”

7. Nutrition Basics

Exclusive breastfeeding about the first 6 months (or iron-fortified formula); no cow’s milk before 12 months (iron deficiency); no honey before 12 months (botulism)
Solids around 6 months; introduce one new food at a time; early introduction of allergenic foods like peanut (per AAP/NIAID guidance, especially for high-risk infants with provider input)
Toddlers: whole milk at 12 months to ~2 yr (unless advised otherwise), limit milk (~16–24 oz/day) to prevent iron-deficiency anemia; avoid choking foods (whole grapes, hot dogs, nuts, popcorn)
Physiologic anorexia in toddlers (slower growth) is normal — offer finger foods, small portions

8. Memory Aids

Erikson “TAIIIG”: Trust, Autonomy, Initiative, Industry, Identity (then Intimacy, Generativity, Integrity for adults)
Piaget “Sensible People Can Fly”: Sensorimotor, Preoperational, Concrete, Formal
Weight: “Double at 6, triple at 12”
Drawing shapes: “Circle at 3, Cross at 4, Triangle at 5” (square ~4–5)
Play: “Solo → Side-by-side → Story/associative → Squad (cooperative)”
Fears: Toddler — “Don’t leave me”; Preschool — “Don’t hurt me”; School-age — “Let me help”; Teen — “Don’t look at me”

9. NCLEX-Style Practice Questions

1. A parent of a 9-month-old asks which skills to expect. Which is most consistent with typical development?

A. Walks independently and says 10 words
B. Sits without support and pulls to stand
C. Copies a circle
D. Rides a tricycle

Answer: B. Around 9 months most infants sit alone, crawl, and pull to stand. Independent walking comes ~12–18 months, a circle ~3 years, a tricycle ~3 years.

2. A hospitalized 2-year-old cries loudly and clings to the parent when the parent tries to leave. What is the best interpretation?

A. The child is being spoiled
B. The protest phase of separation anxiety, an expected response
C. A sign of developmental delay
D. The child is in the detachment phase

Answer: B. Toddlers commonly show protest (crying, clinging) when separated. Encourage rooming-in and consistent routines. Detachment (D) looks like apparent “adjustment” and is concerning.

3. Which toy is most appropriate for a 4-year-old in the hospital?

A. A 500-piece puzzle
B. Puppets and dress-up clothes
C. A rattle
D. A mobile above the bed

Answer: B. Preschoolers learn through imaginative play (initiative). Puppets also let them act out fears. A complex puzzle suits school-age children; rattles and mobiles suit infants.

4. A 5-year-old scheduled for a blood draw asks, “Will all my blood come out?” Which nursing action is best?

A. Explain the anatomy of veins in detail
B. Tell the child not to worry about it
C. Reassure the child that the hole will close and place a bandage after the draw
D. Postpone the draw until the child is calm

Answer: C. Preschoolers fear bodily injury and think magically; a bandage reassures them that their body is “closed” again. Detailed anatomy (A) is for older children.

5. Which findings in a child should the nurse report as possible developmental red flags? Select all that apply.

A. 18-month-old who is not walking
B. 6-month-old with stranger anxiety
C. 2-year-old who used words last month but has stopped talking
D. 3-year-old who has an imaginary friend
E. 12-month-old who does not respond to their name or point

Answer: A, C, E. Not walking by 18 months, loss of skills, and lack of response to name/pointing need evaluation. Stranger anxiety (B) and imaginary friends (D) are normal.

References

Boehning, A. P., & Chamarthi, V. S. (2026). Developmental milestones. In StatPearls. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK557518/

Centers for Disease Control and Prevention. (2026). CDC’s developmental milestones. Learn the Signs. Act Early. https://www.cdc.gov/act-early/milestones/index.html

National Council of State Boards of Nursing. (2026). 2026 NCLEX-RN test plan. https://www.nclex.com/test-plans.page