“There have always been dazzling Windsors, and dull ones,” says Prince Philip matter-of-factly to Queen Elizabeth II (Olivia Colman) in Season 3 of the Netflix series The Crown. Yet the “dazzling” Windsor to whom Philip is referring isn’t his wife, but her sister, Princess Margaret. In seasons 1 and 2 of the hit show, the storyline involving Margaret — whom TIME once dubbed “a Royal Lightning Rod” — detailed her rebellious streak, setting the scene for her unconventional marriage to photographer Antony Armstrong-Jones, known by the time Season 3 begins as Lord Snowdon.