Imagine it's Christmas.

Imagine you have bought your small daughter one of those fancy scooter thingies the kids are all zipping around on.

Imagine you have also, being a responsible parent, bought her a set of knee and elbow pads, and of course, a nice, shiny, properly fitted, never been worn Stackhat.

Watch her play happily with her brother for a change, instead of being pushed around, shouted at, and ignored by turns.

Imagine the happy glow you feel.

Then imagine it's Boxing Day.

Visualise your children running outside, smiling at one another, grabbing the scooters and...

"Where's your helmet?"

Imagine a long, long pause, filled with anxiety

Imagine, if you can bear it, eleven days of searching for the missing helmet. Imagine the tears, the dejection ; cupboards turned out, and wastepaper baskets emptied on the floor. Phone calls made to relatives "just in case"

Imagine the disappointment.

Imagine the scooter gathering dust in the corner.

Then imagine yourself realising that, yes, the helmet is gone. Some horrible person must have stolen it from the front garden on Christmas day.

It feels pretty bad, doesn't it?

So you take your daughter to the bike shop.

You buy a new helmet, identical to the first.

You bring her home.

"Go and get your knee and elbow pads, and then you may scoot"

Imagine, if you will, the delighted squeak...

"Mummy! I have two helmets now! I found my old one! It was in the box where I put the knee guards, with my roller skates!"

How do you find something which has been lost?

Replace it.