The Lady Emily Lennox (1731-1814) was the second of the famous Lennox sisters, daughters of Charles Lennox, 2nd Duke of Richmond and illegitimately descended from King Charles II of England. In 1747, at what was considered an excessively young age for marriage even for the time, she married James FitzGerald, the immensely wealthy Earl of Kildare and went to live in Ireland.

The marriage was a happy one, despite FitzGerald's inability to be sexually faithful. The couple had nineteen children, and FitzGerald was created Duke of Leinster in recognition of his contribution to the political life of his country. It was partly the duke's influence that led to a rift between Emily and her eldest sister, Caroline. After his death in 1773, Emily caused a minor sensation by marrying her children's tutor, William Ogilvie, with whom she had begun an affair some years earlier. Ogilvie was nine years her junior, and was the natural father of Emily's youngest son from her first marriage. A further two children were born to them after their marriage.

Several of Emily's children predeceased her. One of her sons was Lord Edward FitzGerald, a major figure in the republican movement, who was killed during a nationalist rebellion in 1798.