Margaret Conniffe was a Secretary-Stenographer on King's staff from at least the late 1930s to 1947, (perhaps longer). She was paid by the Privy Council Office. She is mentioned frequently in the diary, usually referred to as "Miss C."
One passage in the diary pays a particular tribute to her. In January 1947, while King was at a dinner, his office received news that General George Marshall had become U.S. Secretary of State. "Miss Conniffe had sent the note in to me at dinner," King wrote. He appreciated that she "seemed to realize that I might like to know" and was "intelligent enough to meet a situation of this kind." (Diary, January 7, 1947)
Other entries, though less detailed, indicate that Margaret Conniffe was a hard-working and well-respected member of the Prime Minister's staff.