Why Kids Lie, And When You Should Start To Worry

The truth about small people and tall tales.

Call them fibs, porky pies, or straight-up lies. All kids tell them. Yet, sometimes the onset of lying is so sudden and intense, it sends parents into a flurry of worry – wondering if their child is a sociopath in the making.

So, here are some truths, according to a psychologist whose speciality is dealing with the little lying rascals.

Penny Van Bergen is a Senior Lecturer in Educational Psychology at Macquarie University, whose expertise is developmental psychology. She has researched why kids lie at different ages, and what behaviour is cause for alarm. “In one sense parents’ kind of freak out a little bit when their kids start to lie but it’s actually a good thing developmentally it shows that that jump in cognitive development has occurred,” she told ten daily.

There’s a general consensus among psychologists that understanding the types of lies kids tell at each stage, and why, can help adults guide children towards a path of honesty.


Van Bergen said the onset of lying begins at around three years of age.

At this age, parents tend to think kids lie to get away with not packing up their toys or to hide the fact they've eaten another chocolate brownie. However, it’s not as straightforward as that.

“Three-year-olds are at that age when they are good at telling lies but terrible at judging when to tell them. They are not sure of what they need to do to ensure people aren’t able to detect the lie,” she told ten daily.

So, what seems outlandish to adults may simply be a child's way of processing new ideas, and not about the brownie after all.

It is often done to test out a new behaviour and to see what happens. -- and this type of boundary-pushing is to be expected.

Van Bergen said it's important parents talk calmly and kindly about why lying isn’t helpful.

“From an early age parents need to be having warm, honest and open conversations about why it’s important to tell the truth and how lies can impact and hurt others, there’s good research to back this.”


Pre-schoolers may lie to get some advantage or to protect themselves against unwanted consequences, such as having their favourite doll taken away. At this age children begin to refine their lying skills.

Another reason they lie at this age may be to enhance self-esteem or try to gain approval from peers. Children who lack confidence may tell lavish lies to make themselves seem more impressive or special. Other children this age may lie out of impulse - the old not-thinking-before-you-talk chestnut.

Van Bergen says it’s tempting to come down hard on lying, especially when children seem to be getting better at understanding how to manipulate situations and people.

“Where the punishment is really strong and harsh, the research shows that children often rebel against that and it can sometimes backfire, they tend to lie even more to get out of trouble and then they start to lie particularly well,” she said.

She said calm and kind conversations about how lying can hurt people, will get much better results.


“We also know that teenagers are much more discerning when they lie they generally have a strong moral compass,” Van Bergen said.

Research has found that teenagers tend to lie about things they consider to be their own personal business.

“Like lying about the friends they are hanging out with and the people they are dating or if they are using, alcohol or drugs.”

And while lying is not only normal, and can be a sign of intelligence, if it seems excessive and other negative things are occurring in a child’s life,  its time to reach out for a professional opinion.

“If the lying is happening at the same time as getting in trouble a school a lot or other things going on then it’s always worth having a chat to a GP, school counsellor or psychologist.”

“It can often be about something else the child is anxious about something or covering up that they are getting bullied and are lying about that – there could be all these other reasons that is driving that kind of excessive lying,” she said.

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