Cecelia "Sissy" Pollard was the daughter of Lord Richard and Lady Louisa Pollard and the sister of Charlotte and Margaret Pollard.
Biography
Cecelia was a member of the League of English Fascists, and had met Adolf Hitler. Torvald, an agent of the Celestial Intervention Agency, tried to threaten Romana's position as the Lord President of Gallifrey. First, he brought the anti-time crisis to light. Next, he changed history slightly. He lured Sissy to Switzerland with a fake telegram from her long-missing sister, Charley. Without that intereference, Sissy would have been committing suicide in Munich to protest war. A meeting with Leela made her realise that her blind eye to the Nazis'crimes made her just as liable as they. Sissy shot herself in this new timeline after writing a farewell letter to Charley. (BFG: A Blind Eye)