Ellen M. Sweeney, born in September 1878, was born in Scotland, the oldest child of William and Susan (Ponsonby) Sweeney, who immigrated to the United States in 1881. In addition to Ellen, they had a son, Philip J., who was born in Scotland.

At the time of the 1900 Federal Census, the Sweeney family resided in Wilmerding Borough, Allegheny County. William was a laborer in a shop. Mrs. Sweeney had given birth to 11 children and 9 were living: Ellen M. (b Sept 1878), Philip J., John P., William A., Edward A., Charles A., Susan, James, and Thomas.

William Sweeney, the father, died in 1905. The mother, Susan Ponsonby Sweeney, died of Diabetes Mellitus on July 11, 1906 at age 49. They are buried at Calvary Cemetery, Pittsburgh.

In 1910, eight of the Sweeney children lived together on Wood Street in Wilkinsburg. Philip worked in a factory, and William was a dentist. The youngest sibling, Thomas, was 11, and the oldest, Ellen, was 31.

Ellen graduated from nursing school in 1915, and then served in the Army Nurse Corps during World War I.

"Ellen M. Sweeny" 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." She is named in this article:

In 1930, Ellen M. Sweeney was living with her widowed brother, Phillip, and his son, Phillip J. on LeRoi Road, Allegheny County. - Ellen's age was misstated as 78; she would have been about 52.

Ellen, while living on LeRoi Road in 1934, filed an application for compensation for her World War I service. She was born in Scotland in 1878, but apparently said she was born in 1882 when she enlisted, perhaps to avoid exceeding the age limit.

Miss Ellen M. Sweeney, born September 19, 1878, died on April 15, 1962 in Lakeland, Florida. She is buried at Calvary Cemetery, Pittsburgh.