Is There a Little Pinocchio in All of Us?

Kids Who Uncover 'Innocent' Lies Might Turn Cynical

And Heyman said during the interview that she really thinks all parents lie from time to time, including herself, and that is supported by other research into the pervasive world of lies, big and small.

So is it worth looking specifically at parents? Heyman said "yes," because kids have a lot to deal with in those early years, and a child who uncovers an "innocent" lie might tend to turn cynical.

Related

Holy Bat Cave! Bats Louder Than Rock Band

How Deceptive Can an Orchid Be?

Could Solar Energy Power the Country?

"Some kids probably figure out that their parents are lying at a very young age, maybe 3-year-olds," Heyman said. She added that she tries never to lie to her three kids, because the issue dominates much of her research so she's a bit obsessive, but it isn't always possible. Sometimes, even a hardliner on truthfulness has to bend the rules to spare the feelings of the kid.

Her fellow researcher, Kang Lee, director of the Institute of Child Study at the University of Toronto, admits to also having had a problem always telling the truth. He told a Toronto reporter that he once told his young son to sit quietly in his car seat because the button on his seat belt was actually an "eject" button.

So why do we say such things? Because it makes life a lot easier.

Kids Go Through 'Mental Gymnastics' to Sort Through Mixed Signals

As author A. J. Jacobs told ABC News' David Wright recently, when he decided to spend a year observing the ninth commandment - which he interpreted as Do Not Lie - it was the "worst experience of my life."

Try telling your mate that fat is beautiful.

So you lost the game, 57 to zero, but you played well. Right.

We lie, according to many studies, because we think we have to. Our social graces demand it. Even if we are children.

Adults can excuse a little lying because we're sensitive and don't want to hurt someone's feelings. But kids have it tougher. They have to go through "mental gymnastics" just trying to sort through a batch of mixed signals, Heyman said.

"The big question that motivates me is kids have to figure out the social world," she said. "Unlike a lot of other things, like math, where they get a lot of direct instructions, in the social world they get little direct instruction and the instruction they do get is often completely going to get them in trouble, or it is misleading. They are told never to talk to a stranger, but then they are expected to talk to a stranger in a variety of circumstances or the parents get mad at them if they don't. It's just really confusing."