When Republican Lindsey Graham suggested his sister "could play" first lady if his long-shot presidential bid proves successful, the life-long bachelor knew what he was talking about. Daughters, daughters-in-law, sisters and nieces all have subbed as first lady for America's bachelor and widowed presidents.

James Buchanan, a Democrat who served one term just before the Civil War, never married. His niece, Harriet Lane, filled the first lady's role.

Grover Cleveland, a Democrat who served two non-consecutive terms after the war, began his first term as a bachelor and ended it with a wife. His sister, Rose, was the hostess until Cleveland wed 21-year-old Frances Folsom a year into his term.