Yellowstone star Kevin Costner's wife, Christine Baumgartner Costner, has filed for divorce from the actor, TMZ reports. They've been married 18 years, having wed in 2004.

She cites "irreconcilable differences" as her reason for filing. A representative for Costner confirms the split, offering the following quote to TMZ:

"It is with great sadness that circumstances beyond his control have transpired which have resulted in Mr. Costner having to participate in a dissolution of marriage action ... We ask that his, Christine's and their children's privacy be respected as they navigate this difficult time."

The couple have three children, 15, 14 and 12. Both parties are seeking joint custody, and a prenup is reportedly in place.

The news comes amid ongoing career drama for Costner, whose standoff with the producers of Yellowstone has been making headlines since February. The Oscar winner has reportedly been unable to come to an agreement over his shooting scheduling for the second half of Season 5 due to a conflict with another project of his called Horizon, and according to multiple reports, they've been considering killing off his character and ending the show at the conclusion of Season 5. According to those reports, the network wants to move on with Matthew McConaughey joining the Yellowstone franchise.

Sources tells Showbiz411 that Costner's character, John Dutton, is expected to die in the first few episodes after the show returns from its current hiatus, though it's not yet clear when that will be. The rest of the season will play out the repercussions from his death, and Yellowstone could continue for one more season without him.

Per a source, “We all knew Kevin would leave eventually."

As part of Taste of Country's comprehensive coverage of all things Yellowstone, check out our Dutton Rules podcast on Apple Podcasts and Spotify.

PICTURES: See Inside Kevin Costner's Spectacular Colorado Ranch

Yellowstone star Kevin Costner lives the ranch life when he's off the set of the hit show, too. The Oscar-winning actor owns a 160-acre ranch in Aspen, Colo., that's a spectacular getaway, complete with a main residence, a lake house and a river house.

The luxury retreat also features a baseball field, a sledding hill, an ice rink, multiple hot tubs and views of the Continental Divide. The ranch property comfortably sleeps 27 people, and it's currently available to rent for 36,000 a night.

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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