Theodore Roosevelt's younger daughter and only daughter of his marriage to Edith.

Ethel's indomitable spirit in the face of tragedy has been chronicled, and a number of triumphs.

During World War I, Ethel, now a nurse served in France in the same hospital as her husband served as a surgeon. Later, she became involved with the Red Cross, and served as Nassau County Chairman during World War II, and then as Chairman of the Nassau County Nursing Service. Her long involvement, even while traveling, is shown by her correspondence still residing in the Nassau County Red Cross archives. When the Red Cross recently brought her Fifty Year Service Pin to Sagamore Hill, they had to correct themselves - it was not fifty years of service, it was sixty. When it came time to have her portrait painted, she did not choose to wear an evening gown and jewels, she wore her Red Cross uniform.

She put in many years of work to turn Sagamore Hill into a National Historic Site.

Ethel was one of the first two women to serve on the Board of Trustees of the American Museum of Natural History.