The Doctor's sisters

The Thirteenth Doctor once mentioned having had sisters. (TV: Arachnids in the UK)

She told her companions she had lost all her family, "a long time ago". (TV: The Woman Who Fell to Earth)

Irving Braxiatel, the Doctor's brother, hinted to the Oracle of the Lost that he had lost either a daughter or a sister. (PROSE: Tears of the Oracle)