Understanding what people are trying to do
Lab studies find signs that babies understand what someone is reaching for by about 6 to 9 months. By 18 months, toddlers who watch an adult try and fail to do something will often do it for them.
We haven't yet found studies that measured the age when most children start. The sections below say what is known.
How sure are we?
Not sure yet. No study has yet measured the age when children start; each tested one age group in a lab. How we know this
What it’s a sign of
Your child is learning that people's actions have aims, which helps them learn from others and work with them.
Studies that measure where babies look find signs of this months before children show it by acting it out. These measure different things, so the ages aren't really in conflict.
We don't know the age by which most children understand this, or how much children vary. Later attempts to repeat the looking studies haven't yet been checked for this page.
A classic study on this
Infants selectively encode the goal object of an actor's reach
Amanda L. Woodward · 1998 · Cognition
- Children
- Not given in the summary we read
- Where
- Not given in the summary we read
- Ages
- 5 to 9 months
- How
- Researchers measured how long babies looked at different scenes
- What it found
- Babies of 6 and 9 months treated a reaching hand as aiming for a particular toy, with weaker signs at 5 months.
- Limits
- We have only read the summary.
A classic study on this
Taking the intentional stance at 12 months of age
György Gergely, Zoltán Nádasdy, Gergely Csibra, Szilvia Bı́ró · 1995 · Cognition
- Children
- Not given in the summary we read
- Where
- Not given in the summary we read
- Ages
- 12 months
- How
- Researchers measured how long babies looked at different scenes
- What it found
- By 12 months, babies seemed to expect someone to take a sensible route to what they wanted.
- Limits
- We have only read the summary.
A classic study on this
Understanding the intentions of others: Re-enactment of intended acts by 18-month-old children.
Andrew N. Meltzoff · 1995 · Developmental Psychology
- Children
- About 100 toddlers
- Where
- A lab in Seattle, United States
- Ages
- 18 months
- How
- Researchers tested each toddler once in a lab
- What it found
- Toddlers who only saw an adult try and fail to do something with a toy did the full action themselves about as often as toddlers who saw it done. They did this far less after watching a machine.
- Limits
- Tests one age only, so it shows what 18-month-olds can do, not when children start.
If you’re worried about your child, talk to your child and family health nurse or GP.
Last checked 2 November 2026