Biting is one of the most distressing — and most developmentally normal — behaviours in group care. BC's health authority notes most children under 3 bite someone at least once, and the developmental research (summarized in Canada's Encyclopedia on Early Childhood Development) shows physical aggression rises until roughly 30–42 months, then declines as language, impulse control and emotion regulation come online. Translation: a biting toddler is usually a child whose feelings outran their words — and the evidence-backed response is calm, consistent, and aimed at building those words.
No daily-report notification lands harder than "your child was bitten" — except possibly "your child bit." Here is what the developmental evidence actually says, because it changes how the whole conversation should go.
It is (genuinely) normal
BC's provincial health resource is blunt: most children younger than 3 bite someone at least once, and most stop on their own. The reasons shift with age — around 5–7 months it is usually mouth discomfort; from about 15 to 36 months it is frustration, big feelings, or wanting control over another person.
The aggression curve
The wider research, synthesized in Canada's Encyclopedia on Early Childhood Development, places biting inside a known arc: physical aggression increases across the first 30–42 months of life, then declines as children gain attention regulation, impulse control and — crucially — words. The toddler who bites is not off the curve; they are on it, at its peak, before language has caught up to emotion.
What works
Across the clinical and early-childhood guidance the response converges: stay calm, respond the same brief way every time, attend to the bitten child first, name the feeling and give the script ("you wanted the truck — say 'my turn'"), and engineer the environment around known triggers (transitions, crowding, scarce toys). Punishment and biting-back teach fear, not regulation. And the watch-line: frequent biting, or biting past age 3, moves it from developmental to "ask a professional."
What to do with this
If your child bit — or was bitten — it is not a verdict on your parenting or the program. Reasons differ by age: mouth discomfort in infancy, frustration and control in the toddler years. Respond the same way every time, briefly and calmly ("no biting — biting hurts"), comfort the bitten child first, and give the biter words for the feeling. Frequent biting past age 3 is worth raising with your doctor.
Track the pattern, not just the incident: time of day, transition, crowding, which peers — most biting clusters around predictable triggers you can engineer away (shadowing at transitions, duplicate popular toys, smaller groupings). Keep your incident reports factual and name the developmental context for parents; it turns an accusation moment into an education moment.
Your biting policy should say out loud what the research says: it is common, developmental, handled with supervision changes — and confidentiality protects both families (no naming the biter). Train staff on a single consistent response and put the policy in the handbook before the first incident, not after.
Sources
- HealthLink BC — Biting (most children under 3 bite at least once; reasons by age) — www.healthlinkbc.ca
- Encyclopedia on Early Childhood Development — Aggression (topic synthesis, updated 2025) — www.child-encyclopedia.com
- Tremblay — The Development of Physical Aggression from Early Childhood to Adulthood (Encyclopedia on Early Childhood Development) — www.child-encyclopedia.com
- NAEYC — Understanding and Responding to Children Who Bite — www.naeyc.org
Every claim above is drawn from the linked sources. This article is general information, not medical or legal advice — for concerns about an individual child, talk to your paediatrician or family doctor.
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Start free — no card needed → See the live demoFrequently asked questions
- Is biting normal in toddlers?
- Yes — BC's HealthLink notes most children younger than 3 bite someone at least once, and developmental research shows physical aggression typically peaks in the toddler years before declining as language develops.
- Why do toddlers bite?
- It varies by age: infants may bite from mouth discomfort (teething); from roughly 15–36 months biting is usually frustration, big emotion, or wanting control — feelings that outrun a toddler’s words.
- When is biting a concern?
- HealthLink BC suggests biting that continues past age 3, or happens frequently at any age, deserves a conversation with a health professional.