16 December

On Friday 16 December 2011, Brigadier Alistair Gordon Lethbridge-Stewart died in hospital. (PROSE: Acceptance, and then Understanding, TV: The Wedding of River Song, The Power of Three, Death in Heaven, PROSE: The Day of the Doctor) The Brigadier was with his daughter, Kate Stewart, when he passed, discussing the possibility that the Doctor might come to visit him. His last words were, "Maybe tomorrow". (PROSE: The Day of the Doctor)

According to a calendar on the Snowcap base, 16 December 1986 was a Tuesday. (TV: The Tenth Planet)

In 2006, aboard the SS Elysium, Ruby Duvall came across a book by Lao Tzu in the ship's library. She also noticed an extra light on the lift control panel that required a code to activate; there was a whole other floor down below. (PROSE: Iceberg)

Behind the scenes
In the real world, Nicholas Courtney, who played the Brigadier, was born on 16 December.