Family

It was Vastra's contention that the family one chose for oneself tended more towards congeniality than did, commonly, the family one had simply inherited at birth. (AUDIO: Dining with Death) By this time, Vastra had disavowed her original Silurian clan. (AUDIO: A Photograph to Remember) She chose to build a new family with Jenny Flint and Strax, (AUDIO: Inside Every Warrior) based at 13 Paternoster Row, their shared home. (COMIC: The Lost Dimension)

Helen Sinclair and Liv Chenka, who travelled together with the Eighth Doctor, considered one another to be family. (AUDIO: Escape from Kaldor)

Callys Flambo, who believed family was invariably "difficult", thought the notion of choosing one's family was a curious one. (AUDIO: Dining with Death)

"ChatGuest1" doubted John Lumic knew the meaning of "family". (GAME: Cybus Spy)

The Doctor
The Doctor once had a family, but had lost them "a long time" before their thirteenth incarnation. (TV: The Woman Who Fell to Earth)

Indeed, the First Doctor had at least three grandchildren, Susan, (TV: "An Unearthly Child", et al.) John and Gillian, (COMIC: The Klepton Parasites, et al.) and the Tenth Doctor recalled having once been a father. (TV: Fear Her, The Doctor's Daughter) The Doctor's children were "sons or daughters, or both". (PROSE: The Eleventh Tiger)

The Doctor may have had a human mother, (TV: Doctor Who, PROSE: The Infinity Doctors) a Time Lord father, a grandfather, (PROSE: Cold Fusion) and sisters. (TV: Arachnids in the UK)

Another account suggested that he only had forty-four cousins, as he was loom-born. (PROSE: Lungbarrow, Celestial Intervention - A Gallifreyan Noir) The Eighth Doctor could not recall which origin was a dream, and which was real. (PROSE: The Shadows of Avalon)

The Eighth Doctor was also the adoptive father of Miranda Dawkins, (PROSE: Father Time) and Jenny was the Tenth Doctor's daughter via progenation. (TV: The Doctor's Daughter)

Sarah Jane Smith identified the Tenth Doctor's closest friends, who gathered together to combat the 2009 Dalek invasion, as his family on Earth. (TV: Journey's End)

The Thirteenth Doctor considered her friends to be her extended family. (TV: Resolution)

Raxacoricofallapatorious
Raxacoricofallapatorian families used hyphenated surnames. One family, the Slitheen, functioned as a criminal organisation in what Jocrassa Fel-Fotch Passameer-Day Slitheen referred to as a "family business". (TV: World War Three) This put them at odds with other families such as the Hostrozeen, the Blathereen, and the Hazrateen, who the Slitheen knew as cousins. (TV: Revenge of the Slitheen, AUDIO: The Taste of Death)