The royals of The Crown suffer a huge loss in season four with the assassination of Lord Mountbatten, aka "Uncle Dickie," and no one is hit harder than Prince Charles. In real life, as on the show, Charles was particularly close to this uncle of his, and although some of the specific conversations between them were made up for dramatic purposes, their relationship was largely what is shown on screen.

Charles was actually related to Lord Mountbatten through both of his parents, albeit distantly, since the Queen and Prince Philip are distantly related themselves. As a descendant of Queen Victoria, Mountbatten was related to the Queen, whose line descends from Alice's brother, Edward VII. Technically, Mounbatten and the Queen were second cousins, once removed. His relationship through Philip's side of the family is much clearer: Mountbatten was the brother of Princess Alice, Philip's mother, making him Charles's great-uncle.

In Jonathan Dimbleby...