i) births and deaths

14 February 1942: birth of Michael E. Briant, who directed Colony in Space (Third Doctor, 1971), The Sea Devils (Third Doctor, 1972), The Green Death (Third Doctor, 1973), Death to the Daleks (Third Doctor, 1974), Revenge of the Cybermen (Fourth Doctor, 1975) and The Robots of Death (Fourth Doctor, 1977).

ii) broadcast anniversaries

14 February 1970: broadcast of third episode of Doctor Who and the Silurians. Quinn, who is shielding the wounded Silurian, is found dead by the Doctor.

14 February 1976: broadcast of third episode of The Seeds of Doom. The Doctor and Sarah return to England, and are captured by Harrison Chase as the second pod begins to open…

14 February 1981: broadcast of third episode of The Keeper of Traken. The Keeper dies, Kassia replaces him and is in her turn replaced by the Melkur.

14 February 2002: webcast of first part of "Planet of Blood", the second episode of Death Comes to Time. Two London academics are killed by a vampire; meanwhile the Doctor is concerned at an increasing number of black holes.

iii) dates specified in-universe

14 February 1929: the St Valentine's Day Massacre, as witnessed by the Seventh Doctor, Benny and Ace in Terrance Dicks' 1994 novel Blood Harvest.

14 February 1980: birth of Owen Harper, regular in the first two series of Torchwood. (NB that Burn Gorman who plays him was born in 1974, six years earlier!)