Hitting, biting, pushing, snatching — physical aggression is one of the most common worries parents bring up at nursery pickup. Whether your child was on the giving or receiving end, the alarm is real, and so is the guilt. The developmental science here is reassuring once you know it.
Healthbooq supports families in understanding child behaviour and development.
Why Toddlers Get Physical in Groups
Their brakes do not work yet. The prefrontal cortex — the part of the brain that inhibits impulses and stops you doing the thing you want to do — is the last region to mature, not finishing until the mid-twenties. In a 2-year-old, this system is barely online. When they want a toy another child is holding, the grab fires before any "wait, ask first" thought has had time to form.
They have no other tool. Physical action is the first language a child has. A toddler who wants the truck, wants the other child to move, or is annoyed by what someone is doing has no verbal way to negotiate. The push or the bite is communication using the equipment available.
Group settings are genuinely frustrating. Sharing, waiting, having the carer's attention be split — these are real challenges for young children. Repeated low-level frustration without verbal tools to resolve it spills over physically.
Sensory load. Some children get aggressive when overwhelmed. Noise, proximity, unpredictability, hunger, tiredness — when the regulatory budget runs out, the body acts.
The Developmental Peak
Long-running studies of child aggression — Richard Tremblay's longitudinal work in particular — show physical aggression peaks between 18 months and 3 years, and then declines naturally as language and self-regulation come in. Most children who hit at 2 are not hitting at 4, with no special intervention beyond ordinary good adult response.
This does not mean the behaviour should be tolerated — carers need to step in to keep other children safe and to teach alternatives. But the prognosis is good. Your hitter is not destined to be a hitter.
What It Looks Like at Different Ages
- Under 18 months: biting is most common. Often it is teething, sensory exploration, or wild excitement rather than what an adult would call aggression
- 18 months to 3 years: hitting, pushing, snatching dominate. Driven by frustration, possession conflict, and the lack of working impulse control
- 3 to 4 years: physical aggression usually drops as language takes over. Some relational aggression — exclusion, "you can't play" — starts to emerge in its place
What Actually Helps Reduce It
The two interventions that work best over time are language development (giving children the words to negotiate) and emotion coaching (helping them notice and name what they feel before it gets physical). Punishment without those alternatives produces suppression, not real self-regulation — the behaviour goes underground or just transfers to a moment when the adult is not watching.
Key Takeaways
Hitting, biting, pushing, and snatching in young children are extremely common in group settings and almost always developmental rather than a sign of a character or parenting problem. Physical aggression peaks between 18 months and 3 years, then drops as language and self-regulation come in. Most physically aggressive 2-year-olds are not aggressive 4-year-olds.
