Around age three, fitting in with the group starts to matter to little ones, and their behavior shows that many are likely to go along with what their peers say and do. And while the voice of authority from parents or teachers does matter, it may not be as strong a motivator as what other kids are doing.

“Every culture has its do’s and don’ts,” said first author Leon Li, a doctoral student in psychology and neuroscience at Duke.

Li said that there are cultural norms we all follow, that children must be taught, such as what to say when someone sneezes. So Li and his fellow researches wondered, what makes children behave? What motivates a 3-year-old to use her “inside voice” or cover her sneeze or cough?

To understand what motivates preschoolers to fall in line, the researchers conducted a study in the lab of professor Michael Tomasello at Duke, where Li and Duke undergraduate Bari Britvan invited 3.5-year-olds to help set up for a pretend tea party.

The 104 children participating in the study were each given a blue sticker to wear at the start of the study, and told that the people with that color sticker were part of the same team.

Researchers observed as the children decided among different kinds of teas, snacks, cups and plates for the tea party, first on their own and then after listening to the choices of other team members.

After listening to the choices of others, most of the time the children stuck with their first choice. But 23% of the time the children switched their choice to settle for someone else’s. And when they did, they were more likely to go along with the other person when an option was presented as a group norm rather than a mere personal preference, said the study authors.

This behavior held up even when the other person was another child, not an adult, suggesting that the preschoolers weren’t simply acting out of a desire to imitate adults or obey authority.

The findings lend support to an idea about how children develop the moral reasoning capacity that sets humans apart from other animals.

“When an adult says to an infant or a toddler, ‘we don’t hit,’ the child generally does as she’s told out of deference to that person,” said the study authors. “But eventually, by around their third birthday, children start to think in a different way. They begin to understand cues such as ‘we don’t hit’ as something larger, coming from the group, and act out of a sense of connectedness and shared identity.”

So when it comes to getting kids to behave, it may be more about pack mentality than follow the leader — even if that leader is you.