Clara Cordelia Seymour (also Seymore), born Octonber 22, 1883 (or 1885), was the daughter of Nicholas Seymore/Seymour and Mary Craver of Cambria County, Pennsylvania. Clara was born after the 1880 census, and by 1900 was not living at the family home. She was not found in the 1900 census. In 1910, she was living with her sister, Emma Seymour Delozier, wife of Raphael.

Clara Seymour is listed as a nurse in the 1916, 1917 Pittsburgh City Directories. In 1920, Clara Seymour, 36, a trained nurse, worked at a hospital and lived in Pittsburgh with the Thoma family.

"Clara Cordelia Seymour" is named in a 1922 history of the Pittsburgh Red Cross as a St. Francis nurse graduate who was "in active service with the American Expeditionary Forces and in the United States." According to the U. S. Department of Veterans Affairs Death File, Clara was born October 22, 1885 and she served in the Army Nurse Corps during World War I, from October 30, 1918 until August 3, 1919. The Social Security Death Index, as well as the Pennsylvania Veterans Burial Cards, indicates she was born in 1883, but she stated "1885" when she filed an application for compensation for her military service.

While living in New Mexico, Clara obtained her Social Security Card. At the time of the 1940 census of Santa Fe, Santa Fe County, New Mexico, she is listed as a "maid" for a private family. The record indicates she was residing there in 1935.

Clara Cordelia Seymour died December 24, 1972 in Nicktown, Cambria County, Pennsylvania, and she is buried at St. Benedict's Cemetery, Carrolltown, Cambria County.