But Once a Year (short story)

But Once a Year was the second short story in the Short Trips anthology Short Trips: The Ghosts of Christmas. It was written by Colin Harvey. It featured the Seventh Doctor and Ace.

Summary
For the last few years, at Christmas time, the Merrison family has been visited by something that each year takes away one of their children. Only David, a wheelchair user, is left, and his parents have become distant.

This year, before the creature arrives, David is visited by the Doctor and Ace. He tells them the story of his brothers and sister. When the creature arrives, it takes Ace instead of David.

The Doctor deduces that a skull that had been collected by David's grandfather is actually an alien artefact. The creature wants the skull, so when it returns, the Doctor offers the skull in exchange for Ace and the Merrison siblings. They return safely, having spent the intervening time in the alien's spaceship, where they worked as its slaves. With the missing children returned, the Merrisons become a family again.

Characters

 * Seventh Doctor
 * Ace
 * David Merrison
 * Lucy
 * David Merrison's father
 * David Merrison's mother
 * Steven Merrison
 * Noel Merrison
 * Elizabeth Merrison
 * Mr Lobson

Worldbuilding

 * David's grandfather adventured with Augustus Glavin on the HMS Rochester. He collected fossils.
 * David's father reads The Times.
 * The Doctor mentions Good King Wenceslas.

Continuity
to be added