Sumner married Cid Ricketts (born Bertha Louise Ricketts in Brookhaven, Mississippi) when she attended medical school at Cornell. They married on July 10, 1915 and had four children. They were divorced in 1930, but she kept her married name. Cid Ricketts Sumner went on to become an author, writing books that included Tammy Tell Me True, which was made into the movie Tammy and the Bachelor, and Quality, which became the movie Pinky. Cid Ricketts Sumner was murdered by their grandson, John R. Cutler, in 1970.