'Sister Wives' daughter, Mariah, comes out as a lesbian

To say the Brown family was thrown for a loop on the most recent episode ofSister Wivesis an understatement.

Fans of the TLC show -- as well as the Brown family themselves -- were shocked by Sunday's big reveal, when Kody and Meri's 21-year-old daughter, Mariah, came out as a lesbian. Mariah is currently a college student in Utah.

"This feels so awkward," Mariah nervously told Cody, Meri, as well as Cody's three other wives, Janelle, Christine and Robyn before the pivotal moment. "Um, I'm gay."

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In previews of next week's episode, Meri is struggling with the news. "I thought I knew my daughter, I didn't," she cries.

See photos of the "Sister Wives" cast:

Meri also gets upset with Kody and Robyn for appearing to be happy when Mariah comes out.

"We're not happy that Mariah's gay, we're happy that she knows herself," Kody responds.

Mariah is one of 18 children in the polygamist family. She is the only biological child of Meri, Kody's first wife. On Sunday, Mariah took to Twitter to thank fans for their support.

"Wow okay y'all making me cry with your support," she wrote, adding a rainbow flag emoji. "Thank you thank you thank you thank you."

"As hard as 2016 was for me, it was also probably the best year of my life," she also tweeted on New Year's Eve. "I am genuinely so blessed."

In a July 2013 HuffPost Live interview, the Fundamentalist Mormon family showed support for gay marriage. "We have established our family the way we've chosen to, we've organized it the way we wanted to, we believe that all people should be allowed to have that right," Kody said.

"All adults should be be able to choose who they love and how they structure their family," Robyn added. "I have some very close friends who are homosexual."

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This, of course, isn't the first time the Brown family has dealt with surprising news. In 2015, Meri revealed she was tricked into having an online relationship with a woman. Watch the video below to see her tearfully discuss the catfishing incident.