Eleanor and Franklin D. Roosevelt

Eleanor Roosevelt began courting her father's fifth cousin, 20-year-old Harvard student Franklin Delano Roosevelt, in 1903. The couple got engaged in November, married on St. Patrick's Day 1905, and produced six children, five of whom survived infancy. In 1921, while vacationing in Campobello Island, New Brunswick, FDR contracted an illness that resulted in permanent paralysis of his legs. Another blow followed: FDR's affair with Eleanor's social secretary, Lucy Mercer. The marriage endured, however, and as President and First Lady, they used their influence to promote New Deal policies and advocate for civil rights.