Lord President's daughter
After the Doctor retired to Gallifrey, he fell in love with the Lord President's daughter, but she and nearly every other Time Lord was killed by an alien race. After the Time Lords retreated into the Matrix, (PROSE: Doctor Who - The Ninth Doctor) they sent him, and the Master, on dangerous missions as punishment for the death of (WC: Scream of the Shalka, PROSE: Scream of the Shalka) the Lord President's daughter. (PROSE: Doctor Who - The Ninth Doctor)
The Twelfth Doctor later told Clara Oswald that a rumour spread by the Shobogans that he had stolen "the President's wife" was a distortion of the truth that he had stolen "the President's daughter". (TV: Hell Bent) However, one Time Lord historian believed this was a reference to Susan Foreman and how the First Doctor had spirited her away from Gallifrey when he originally escaped from the Capitol. (PROSE: A Brief History of Time Lords)