Being told that your child has hit, bitten, or pushed another child at daycare is alarming for most parents. It is natural to wonder: is something wrong? Is this normal? Is my child becoming aggressive? Understanding the developmental basis of aggression in toddlers and young children — and how it typically unfolds — helps parents and carers respond effectively rather than reactively.
Healthbooq supports families in understanding and managing toddler behaviour.
Why Young Children in Group Settings Are Often Physically Aggressive
Limited verbal communication
Before language is sufficiently developed to negotiate verbally, children communicate through action. A toddler who wants a toy, cannot yet say "Can I have a turn?", and whose other signals are not being read, may simply take the toy — or hit the child who has it. This is not malice; it is a communicative act using the tools available.
As language develops, physical communication is replaced by verbal. This is why aggression typically peaks in the toddler years and declines in the preschool years — not because of moral development, but because verbal tools become available.
Immature impulse control
The capacity to inhibit an impulse and substitute an alternative behaviour is a function of the prefrontal cortex, which matures slowly across childhood and adolescence. In toddlers, this capacity is minimal. The child sees something they want, the impulse to take it is immediate, and the inhibitory capacity to stop that impulse is underdeveloped. The grab or hit happens before any reflection is possible.
This is not wilful naughtiness. It is neurological immaturity. Punitive responses that treat it as deliberate moral failure are both ineffective and developmentally inappropriate.
Group resource sharing
A group setting introduces genuine resource scarcity that the home environment does not have in the same way. One attractive toy, many children who want it. The daycare environment creates the conditions for conflict — and in children with limited language and impulse control, conflict produces physical behaviour.
Adaptation stress
A child who is in the process of adapting to daycare — carrying more stress than usual, with depleted regulatory resources — has even less capacity for impulse control than they normally would. Aggressive behaviour often increases in the early weeks of daycare and decreases as adaptation progresses. This pattern is predictable and does not indicate a persistent problem.
Biting specifically
Biting is particularly alarming to parents and carers, but it has specific developmental drivers. It is most common between approximately 13 and 24 months, for several reasons: teething discomfort, the sensory pleasure of biting (which is a normal motor activity for this age), the effectiveness of biting as a communication act (it gets an immediate, powerful response), and the frustration of limited language.
Most children stop biting as a conflict strategy as language develops in the second and third year of life.
What Adults Should Do
Respond promptly but calmly to the incident. Describe what happened clearly without attribution of intent or character ("You hit [name]. Hitting hurts."), attend to the child who was hurt, and separate the children briefly if needed.
Identify the trigger pattern. Most aggressive behaviour in toddlers follows identifiable patterns: particular situations, times of day, resource competition. Understanding the pattern allows the adult to anticipate and prevent rather than just respond.
Support language development. Teaching the words and phrases that replace physical communication ("My turn," "Stop," "I want that") provides an alternative strategy. This takes time and repetition.
Check the environment. If multiple instances of aggression involve the same resource, consider having more of that resource available, or changing the physical environment to reduce the trigger.
When to Be Concerned
Aggression that is age-typical and gradually decreasing does not warrant clinical concern. Indicators that warrant further investigation:
- Aggression that is sustained and increasing rather than age-typical and decreasing
- Aggression that targets specific children deliberately
- High severity (causing injury consistently)
- Significant emotional dysregulation alongside the aggression
Key Takeaways
Physical aggression — hitting, biting, pushing, grabbing — is common in toddlers and young children in group settings and is typically developmental rather than indicative of a behaviour disorder. The primary causes are limited language, immature impulse control, and the genuine challenges of resource sharing in a group. Understanding the developmental causes helps adults respond supportively rather than punitively.
