Dot Cotton

Dot Cotton was either a fictional character on EastEnders, (PROSE: The Blood Cell) or a real individual who was an acquaintance of the Doctor. (TV: Sprout Boy Meets a Galaxy of Stars)

Biography
Dot met the Twelfth Doctor at a dinner party with Sprout Boy. (TV: Sprout Boy meets a Galaxy of Stars)

Information from invalid sources
While the Eleventh Doctor was trying to drop off Dermot O'Leary at the National Television Awards, Dermot stepped out of the TARDIS into Albert Square where he was met by Dot. He was shocked to find that she knew the Doctor. Dot explained to him that he was never out of her laundrette. (NOTVALID: Dermot and the Doctor)