The most disturbing reason children lie is that parents teach
them to. According to Talwar, they learn it from us. "We dont
explicitly tell them to lie, but they see us do it. They see us tell
the telemarketer, 'I'm just a guest here.' They see us boast and lie
to smooth social relationships."
Consider how we expect a child to act when he opens a gift he
doesnt like. [...]
Meanwhile, the child's parent usually cheers when the child
comes up with the white lie. "Often, the parents are proud that their
kids are 'polite' -- they don't see it as lying," Talwar remarks.
She's regularly amazed at parents' seeming inability to recognize that
white lies are still lies.
[...]
Encouraged to tell so many white lies and hearing so many
others, children gradually get comfortable with being disingenuous.
Insincerity becomes, literally, a daily occurrence. They learn that
honesty only creates conflict, and dishonesty is an easy way to avoid
conflict. And while they don't confuse white-lie situations with lying
to cover their misdeeds, they bring this emotional groundwork from one
circumstance to the other. It becomes easier, psychologically, to lie
to a parent. So if the parent says, "Where did you get these
Pokémon cards?! I told you, youre not allowed to waste your
allowance on Pokémon cards!" this may feel to the child very
much like a white-lie scenario -- he can make his father feel
better by telling him the cards were extras from a friend.