It looks like Dutton Ranch is expanding: Yellowstone actor Luke Grimes and his wife, model Bianca Rodrigues, are expecting their first child together.

Rodrigues announced the news on Instagram over the weekend, sharing a photo of a silhouette of her baby bump and writing, "Can't wait to meet you little one."

The couple wed in 2018.

Grimes, 40, stars as Kayce Dutton, son of John (Kevin Costner) and Evelyn Dutton (Gretchen Mol), on Yellowstone, the hit neo-Western series created by Taylor Sheridan. Grimes' previous screen roles include Navy SEAL Marc Alan Lee in American Sniper; Elliot Grey, brother of Christian Grey, in the Fifty Shades of Grey franchise; and vampire James Kent on True Blood.

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Yellowstone will return with the second half of its fifth and final season Nov. 10 — sans Costner, who announced his departure in June. The rest of the cast, including Grimes, Kelly Reilly (Beth Dutton), and Wes Bentley (Jamie Dutton), is expected to return for the final frontier, wrapping up the multigenerational saga of of a ranching family in Montana.

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Grimes told PEOPLE earlier this year that he was "ready to tell the end of the story."

"For seven years, we've been doing this, and we started in 2017. That's crazy," he said. "It's changed my life in every way possible. Nothing will ever be the same because of this show in all sorts of ways, good and bad. I will miss it terribly."

The actor and his wife relocated to Montana to Yellowstone, and the two intend to stick around after it ends. "My wife and I love it out there," Grimes told PEOPLE. "I think it'd be a great place to raise a family."