Lady Sarah Lennox (1745-1826) was the most notorious of the famous Lennox sisters, daughters of Charles Lennox, 2nd Duke of Richmond .

Brought up by her elder sisters after the deaths of both parents, Sarah was introduced at court and caught the eye of the youthful King George III. Her family hoped to see her as queen, but the marriage was discouraged by the King's advisors, who foresaw possible complications as a result of her close relationship with the radical Fox family (her sister Caroline being the wife of Henry Fox). In 1762, Sarah was married off to Sir Charles Bunbury . Within a short time, their marriage was on the rocks, and Sarah's conduct was getting her a bad reputation. In 1769, she eloped with Lord William Gordon , with whom she had been having an affair, and was ostracised by polite society as a result. Eventually she found happiness with an impoverished army officer, George Napier . They were married in 1781, and had eight children, including Charles James Napier.