Harriet Rebecca Lane Johnston (May 9, 1830 – July 3, 1903)

Harriet Rebecca Lane Johnston (May 9, 1830 – July 3, 1903), niece of lifelong bachelor United States President James Buchanan, acted as First Lady of the United States from 1857 to 1861. She was one of the few women to hold the position of First Lady while not being married to the President