One of the most nagging Yellowstone loose ends was just cinched shut when — during an emotional scene between John Dutton and Monica — the family patriarch shares something he's never told anyone before.

Longtime fans of the show may recall hearing that John Dutton (played by Kevin Costner) once had a brother, when at the close of Season 2, his father (played by Dabney Coleman) admitted that he missed him, just before he died. That emotional scene — which featured Chris Stapleton's "Daddy Doesn't Pray Anymore" — is over three years old. It's forgivable if you've long quit wondering.

The Dutton Rules team never forgot, however. During this Season 5, Episode 4 recap episode, Billy Dukes and Adison Haager explore how knowing about Peter Dutton adds context to the series. His story is very short, and very sad.

Who Is John Dutton's Brother?

After Monica (Kelsey Asbille) buries her and Kayce's baby boy, she's approached by her father-in-law. During one of the more tender moments in the history of the series, John shares that his little brother, Peter Dutton, only lived 18 hours before dying because he had a weak heart. The incident forever hardened his mother, but he recalls the birth of his own son, Lee Dutton, and his father telling his wife that Peter lived a perfect life, because all he ever knew was his mother's love.

Monica is moved to tears by this story, one meant to encourage her to prevent her own heart from hardening after losing her baby boy after just an hour of life. The couple mentioned trying for another baby in days after his death (S5, E1), but in Yellowstone time, it's only been a week or two.

John Dutton's mother and father would never have another child, which means that unless there is another late brother or sister we've never heard of, John is an only child.

The death of a sibling is common in the Yellowstone franchise. Now, viewers can add John to Kayce and Beth (Lee Dutton died during the series premiere), Monica (her brother died that same episode), Tate Dutton (baby John Dutton was his brother and the original John Sr. from 1883. John Dutton's wife and Jamie Dutton's birth father also died violently during a show that seems to focus its violence on family first.

What Happened to John Dutton's Father on Yellowstone?

The elder John Dutton (played by Coleman) is listed as John Dutton Sr. in the credits, but he's not the same character depicted by Audie Rick in 1883. Viewers may meet him during 1923, the second Yellowstone prequel (Dec. 18), but as of yet no actor is attached to that name. What is clear is that the elder Dutton ran the Yellowstone Ranch late into life, before passing it on to Dutton's character. He died of natural causes in the mountaintop scene described above and is buried on the family property.

Find Dutton Rules on Apple Podcasts and Spotify, or wherever you podcast. You can also listen at the above player.

22 'Yellowstone' Facts You Probably Didn't Know

How big of a fan of Yellowstone are you? These 22 facts about the Paramount Network show are sure to stump even the most dedicated viewers. They're almost all about the cast members and their real-life passions and roles. John's kids? Beth's accent? Rainwater's guitar playing? Tate's spoilers? It's all part of this list of 22 Facts You Probably Didn't Know About Yellowstone.

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