What Was the Most Consequential Sibling Rivalry of all Time?

Paul Woodruff, philosophy professor, University of Texas at Austin

Castor and Pollux, of course. Castor was human; Pollux was a god. Now, there’s a difference in natural endowment! Most sibling discontent comes down to that. In their case, Zeus took pity and made them both stars. Would that all pairs of brothers were so lucky.

Frank Sulloway, psychologist and author, Born to Rebel: Birth Order, Family Dynamics, and Creative Lives

Charles Darwin’s genius was characterized by his painstaking pursuit of a heretical idea. He appears to have owed some of that persistence—and his ability to withstand scathing criticism—to his older sister Caroline. So zealous was Caroline in her efforts to improve Charles that he later recalled thinking, whenever he encountered her, “ ‘What will she blame me for now?’ and I made myself dogged so as not to care what she might say.”

Zeke Emanuel, oncologist, bioethicist, and vice provost, University of Pennsylvania (and brother of Ari, Rahm, and Shoshanna)

Rachel and Leah, from the Book of Genesis, competed for the attention and affection of the husband they shared, then competed to bear his children. Their relationship shows how the poison of sibling rivalry can be passed down from generation to generation—Joseph, son of the more prized wife, Rachel, was sold by his brothers into slavery.

Jeanine Basinger, film historian

The greatest sibling rivalry in the history of film was between the sisters Olivia de Havilland and Joan Fontaine, who didn’t speak for several decades but competed in all aspects of life. Olivia spoke fluent French, so Joan mastered French cooking. Joan married an actor, so Olivia married a screenwriter. Joan won one Oscar, so Olivia won two.

Jeffrey Kluger, author, The Sibling Effect

John Wilkes Booth followed his big brother Edwin onto the stage but had nowhere near Edwin’s dramatic subtlety. The brothers also differed in their political views: John was fiercely pro-South and started so many arguments that Edwin finally banished him from his New York home. Rootless, John resolved to find a different way to make his name.

Jeremy Schaap, sportswriter

The rivalry between the Klitschko brothers, Vitali and Wladimir, has been consequential even as it has not been fully realized. For most of the last decade, the gifted Ukrainians were easily the best heavyweights in the world—but they refused to fight each other, depriving fans of an epic fraternal encounter and diminishing the world heavyweight championship. They could have made millions by doing what many brothers do free of charge. Why not fight? Because they promised their mother they wouldn’t.

Emily Yoffe, “Dear Prudence” columnist, Slate

In the world of advice-giving, Ann Landers and Dear Abby, the preeminent newspaper advice columnists of the 20th century. Their snappy, earthy, commonsense approach blew up the stolid lugubriousness of the form, and made them two of the widest-read writers of their day. Their competition spurred the ambition of each. But their rivalry was fierce (they once went years without speaking) and flared over the decades, a cautionary lesson that some problems just can’t be solved.

Philippa Gregory, author, The White Queen and The Other Boleyn Girl

The children of Isabella and Ferdinand, the royal family of Spain, could not have been more complicated: The oldest sister, Isabella, married Alfonso of Portugal and upon his death married his brother. Upon Isabella’s death, he married her sister Maria. Their youngest daughter, Katherine of Aragon, married Arthur, Prince of Wales, and upon his death married Henry VIII—who spent his life trying to outdo his own brother’s reputation.

Reader Responses

John Salamack, Albuquerque, N.M.

Romulus and Remus, the mythological twins whose rivalry initiated the rise of the Roman Empire.

John S. Harris, St. Louis, Mo.

If Cleopatra had gotten along better with her little brother, Pharaoh Ptolemy XIII, Julius Caesar might not have demanded a crown, Mark Antony might not have gone native, and the administrative genius of Augustus might never have been discovered—and Richard Burton wouldn’t have met Elizabeth Taylor, making several decades of the 20th century much duller indeed.

Phillip Certain, Madison, Wis.

The first fratricide, Cain’s murder of Abel.

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