Not only do kids lie, they often lie badly. But while sometimes, it's all you can do not to laugh out loud at such poor efforts by your children to be economical with the truth, other times their blatant untruths can feel hurtful. Everyone wants to be able to trust their own children and it can be hard not to take lying personally.
There's a great cartoon that does the rounds on social media from time to time. "He did that," says the young blue crayon character, pointing to his red crayon friend. Both are being brought to task in front of a green parent crayon character. There's a glitch in the blue crayon's argument though. The drawing all over the walls is blue.
Most, if not all, parents will relate to it.
Yet the irony is that many parents' response to their children's fibs does little more than to encourage it, say experts.
"If you are too harsh, too unforgiving and too controlling, you create an air of anxiety in your home and an air of perfection that may be stressful," explains parenting coach, Sue Atkins.
Other parents quite literally set their children up to lie by asking questions about something they've done wrong, to which they already know the answer, she adds. The better response would be to name what they've done, rather than try and trap them into providing information that they know will lead to lead them straight into trouble.
It's also important to remember that very young children' simply don't understand the difference between what truth is and what isn't, she adds.
Many experts call this "healthy lying" as it involves innocent fantasy and imagination, which is important in the development of children. To tell them off for it will only confuse them.
Then there's the fact that many of us parents inadvertently teach our kids how to bend the truth. "Tell Granddad you like the present even if you don't, because he will feel sad otherwise," or "Please don't tell Auntie Jill that you've never worn that jumper she knitted you" are basically teaching them to lie, albeit in certain circumstances.
Atkins – who, as a deputy head and class teacher for 22 years, has heard just about every porky pie you can imagine – says she's learned that all children lie occasionally and there's a plethora of different reasons for it, depending issues including maturity, confidence levels and circumstances.
Whilst younger children often tell lies without even realising, she explains that slightly older children may lie to avoid getting into trouble, or arguably worse, getting someone else into trouble. Other times, children lie to avoid shame or embarrassment or in an attempt to escape your rules, for example, saying they have brushed their teeth or that they didn't help themselves to a biscuit out of the tin without asking.
Children may also lie to avoid your disapproval because they hate the thought of disappointing you.
"Children with low self-esteem sometimes 'lie' or exaggerate the truth, as a way to impress others or to fit in with their friends or school peers," adds Atkins. "Also some children who are feeling insecure may even invent scenarios to try to get your attention and interest – as any attention is better than no attention at all."
Children may also fib in an attempt to be tactful, says parenting author Liz Fraser, who works as a parenting expert for Care.com. "White lies tend to start around the age of six or so, and are generally told to avoid hurting someone's feelings. The old, 'No, your bum doesn't look big in that' for adults. This is quite an important social skill and doesn't need to be curbed much at all. In fact, it shows compassion and understanding of life's little nuances and rules."
In fact, even if the reason for the lie isn't so positive, shouting "How dare you lie to me!" at children really doesn't help, she says. "They need to feel bad about it themselves and to want to stop themselves, rather than to please you."
Focus on teaching children the importance of integrity, honesty and doing the right thing, regularly taking time out to talk about what you expect from them and why telling the truth is important, she advises.
Instead of punishing every single fib, she explains, it's about creating an environment where your kids feel safe telling you the truth. An emphasis on learning from mistakes, rather than just focusing on the mistake itself, can help.
"It's worth pointing out that friends don't like people who lie and that telling the truth is much braver and stronger – and makes people like you much more," adds Fraser.
Always be mindful of the age of the child. A four-year-old, for example, might make up a big fat lie as a way to work out the world around them as part of their normal development. And even an eight-year-old might think in a black-and-white kind of way that makes them say, "I hate Sophie in my class," when she's trying to say that something Sophie did made her sad.
One way round this is to ask questions like, "Are you really trying to say x, y and z?" which helps build up the child's skill of articulation for the next time.
"When they do lie, press an imaginary 'Pause Button' in the moment afterwards, just to give yourself a moment to immediately detach from the situation so you can assess perhaps why they feel the need to lie to you," advises Atkins.
"Praise your child when they tell the truth so they learn that you value honesty and, of course always model honesty and truthfulness yourself," she adds.
The bottom line is lying isn't just a moral issue. It's much more complicated than that. As clinical psychologist at www.childchology.co.uk, Helen O'Connor, says, "The most important thing a parent can do is to teach the child appropriate ways to solve their problems, rather than lying.
"Shouting, and becoming defensive is unlikely to entrust the child to talk to you about problems that they may be having, whereas being open and calm is likely to be effective."