Anne Joyce's daughter

Anne Joyce and Daniel Joyce had a daughter. In 2002, she was in her thirties. As her father was a former Time Lord, she was at least half-Gallifreyan; (PROSE: Unnatural History) her half-brother, also born of a human mother, was the Doctor. (PROSE: The Gallifrey Chronicles)

Behind the scenes
"I gave the Doctor a half-sister because I wanted a real genetic connection to contemporary human life, not to mention the ability to explore the unique convergence of the two life forms. In that way I hoped to say something about the nature of human life as well, what we might be missing, where we might be heading in an evolutionary way. In a series, I would have explored not only the Doctor's relationship with his half-sister, but also her children, in particular an only male child who becomes a future Time Lord renegade."
 * The notion of the Doctor's father and his wife Anne having a daughter on Earth originated in Robert deLaurentis' 1994 script The Time of My Life. In The Nth Doctor, deLaurentis explained this decision:

- Robert deLaurentis