Two reality stars found love in the real world.
"I’m marrying my favorite person in the world," Casillas, 27, captioned an Instagram shot debuting her engagement ring.
She offered a closeup of the diamond on her Instagram Story, writing, "I'm lucky."
Bird, also 27, showed the newly engaged couple celebrating with chocolate on his Story as they vacation in Greece.
Kailah Casillas announces her engagement to Sam Bird.
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Casillas' love life served as a plot point on MTV's The Challenge: Total Madness because she hooked up with fellow competitor Stephen Bear while in a relationship back home with DJ Michael “Mikey P” Pericoloso, whom she'd been dating for more than three years. Casillas and Pericoloso ultimately broke up.
Bird's personal life also played out on TV when he appeared on season 4 of the U.K. Love Island. He started dating Georgia Steel on the show, and although they didn't leave the island together, the two rekindled their romance after filming and moved in together. They called it quits in October 2018 amid accusations of cheating, but Bird and Steel, 22, both appeared on MTV's Ex on the Beach: Peak of Love in 2019.
Kailah Casillas/Instagram The Challenge star's engagement ring
Things didn't work out between Bird and Steel the second time around, and he and Casillas went public with her relationship in January.
The Real World: Go Big or Go Home alum's Challenge costars Jenna Compono and Aneesa Ferreira offered their congratulations on her engagement in the comments section of her Instagram post, with the latter writing, "I'm so excited for you!!"
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