TOMORROW is National Tooth Fairy Day, celebrating the fictitious character that brings money to children who have lost their teeth.

Reading about the tradition reminded me of the day my eldest daughter came back from primary school with the news that one of the boys in her class had received £50 from the tooth fairy.

This threw me, and a number of other parents, into a quandary: how to explain why our kids found only 50p under their pillows.

We all agreed that it was totally irresponsible of the parents to give their child so much, at the same time trying to work out how much the full set of gnashers would set them back.

I suppose it is better than forgetting altogether, which I did one night, believing that my husband had left the money.

The next morning, as my daughter puzzled over it and asked awkward questions, we had to think up a good excuse - I vaguely remember rifling down the back of the bed and pretending the coins had been pushed back during the night.

At least I didn’t take the lazy parents option and do what one was reported as saying - that the tooth fairy was too tired to go upstairs so she left the money on the kitchen worktop.

The tooth fairy is just one of a number of untruths that we steer our children into believing.

Like Father Christmas, it is something about which we take pains to convince them is real.

It’s a strange way to behave, when we are constantly ramming home to children how vital it is to tell the truth.

My husband recently came across some thank you notes that my daughters sent to Father Christmas when they were little.

He was all for showing them what they had asked for, but I stopped him.

I felt that they would think we had let them down if we had not posted them up the chimney as promised.

I can’t remember at what age I stopped believing in Father Christmas.

I think I tried to believe for as long as possible, hanging on to the last threads of childhood. I was sad when my children no longer believed.

Such stories are only white lies, they are well-intentioned, and don’t do any serious damage, although some of them do stick.

I still believe that carrots help us to see in the dark. They do contain vitamin A, which is linked to the pigment in your eyes that operates in low light conditions, but they don’t really help.

I eat a lot of raw carrots, and still have to clumsily fumble my way to the wheelie bin after dark.

And for a long time I believed that sitting too close to the TV ruined your eyesight.

In fact, children are better at focussing on close-up objects than adults. Neither does reading in low light ruin your eyesight.

After being told this year after year, I was convinced that it did, and have warned my daughters many a time, as they read in dimly-lit bedrooms.

I was also convinced - and actually still believe, although there is no truth in it - that standing in front of the microwave while it was on would infuse me with radiation poisoning.

I’m sure I have told my children the same thing.

These myths permeate through the generations. Until recently I genuinely believed that swallowing chewing gum or bubble gum was unwise, and it would not digest properly. But this is, in fact, utter rubbish.

There will always be times when we bend the truth.

The Easter bunny will be along soon - now he’s real enough.

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