THE traditions of Christmas go back many years and readers have urged me to explain one in particular yet again. So here goes.

One December, Santa was having a bad Christmas. Half the elves in his workshop had gone down with flu and the new ones he had set on were making the toys all wrong so that he had dolls with three left feet.

As if that wasn't bad enough, his wife Sanity Claus told him her mother was coming to visit for the holiday. It wasn't that Santa disliked all mother-in-laws, just his mother-in-law, and he knew she would complain, as she always did, about him being out all night on the tiles.

He went out into the snow for a little peace and quiet and checked on the sled and found one of the running boards very dodgy and a runner too loose to risk. And here he was just an hour away from lift off.

Santa got out his tool box and got to work, banging his thumb with the hammer and dropping the solid steel runner on his toe before he finished. His stress levels were building and he knew his face was as red as his coat.

When he nipped back inside Mrs Claus looked out of the window and said: "Goodness. It looks like rain, dear," and burst out laughing as her annual joke caught him out again.

He stomped to the stables for the comfort of his old friends. Dasher and Prancer were all right, but Vixen, Comet and Cupid were hungover from the reindeer Christmas party and Donner and Blitzen still weren't back yet.

"At least I can rely on you, Rudolf," he said. "Your nose is as bright as ever."

"This isn't illumination," said Rudolf, with a sneeze. "I've caught the flu off the elves."

What else could go wrong? thought Santa, as he trudged back to the house, only to find the elves had been at the medicinal brandy and were rolling drunk and the sacks of toys were still only half filled.

It was turning into the worst Christmas ever and he reached for the last brandy bottle to pour himself a snort and calm his shredded nerves when a loud bang on the door caused him to jump and drop the bottle - which smashed on the floor.

This was the last straw and he pulled open the door with steam coming out of his ears.

"Yes?" he roared.

A little fairy was standing on the doorstep pulling a fir tree behind her.

"Hey, Santa? Where shall I put this tree?" she said.

And that's how the fairy came to be on top of the Christmas tree.