Mary Lightfoot Tarleton Knollenberg (June 9, 1904 – December 21, 1992) was an American sculptor. Born in Great Neck, Long Island, Knollenberg was a student of Mahonri Young and Heinz Warneke, and received a Guggenheim Fellowship in 1933. She later married historian , and was stepmother to his son Walter. She was the greataunt of artist Ippy Patterson. During her career she was a member of the National Association of Women Painters and Sculptors, the Sculptors Guild, and the . Later in life Knollenberg counted among her friends Walker Evans. She died in her sleep at her home in Chester, Connecticut. Her work was the subject of a 2014 retrospective at the Florence Griswold Museum.Her papers and journals, along with diaries of her artist-writer mother, Mary Livingston Tarleton née Plympton, a