Christine Brown's Aunt Believes 'Sister Wives' Star Wasn't 'Genuinely Happy' in Kody Brown Marriage

Christine Brown announced her separation from Kody Brown on Instagram Tuesday

Christine Brown's aunt Kristyn Decker is sharing what she believes led the Sister Wives star to end her decades-long polyamorous marriage to Kody Brown.

During an appearance on the Reality Life with Kate Casey podcast Friday, Decker said she wasn't completely surprised by Christine, 49, leaving Kody, 52.

"I could see it coming. I don't think Christine's been genuinely — what I call genuinely happy — for forever, since day one," Decker, who isn't currently in contact with Christine, said.

"It's kind of impossible to have a marriage when you've got a division like that [with] four women — five, whatever it's going to be, and a lot of children," she continued. "That's not a partnership. It's not a real marriage. And so I've just felt bad for her and others from day one. As well, I was in [a plural marriage]. So I had to support that way back when, but it still breaks my heart. I don't think any women are genuinely happy in that."

Decker claimed what fans see on the TLC hit is "not reality," noting how the "true part and the heartache and the sadness" occurs behind the scenes.

"The feelings that Christine and the other women are finally starting to show after all this time — and it started a while back," she said. "I was grateful that some of the truth was coming out in the show about the hardships of polygamy. But for the longest time, they were glamorizing it, and it just wasn't real."

Decker explained how women in these situations are "not supposed to communicate their feelings and sadness." Those who do, she added, are "looked down upon."

Asked to weigh in on why a relationship like Christine and Kody's ended, Decker said: "I think that as soon as another wife comes into the family, the whole dynamics change."

Kody and Christine Brown. Christine Brown/INSTAGRAM. inset: shutterstock

"The marriage is never going to be the same or the relationship. I'm not sure, like I said, you can even call it a marriage. As soon as my husband took a second wife, our marriage was never the same, and it was never going to be. So, I think things start falling apart pretty fast," she continued. "And it just takes time and over the years for women [like] Christine to get stronger and find out this isn't what she wants and she doesn't have to do it. And, 'I'm going to get out of here.' "

Decker also believes Kody's fourth wife, Robyn Brown, "definitely threw another wrench in there and heartaches and depression" upon entering the plural marriage in 2010. "No one wants to have their husband having sex with another woman and having children with them and on and on," she added. "It's done because we believed we had to do it. Christine believed that, that's how she was raised. And so did the other women."

Kody was already in plural marriage with first wife Meri Brown and second wife Janelle Brown when Christine joined in 1994. The exes share son Paedon, 23, and daughters Aspyn, 26, Mykelti, 25, Gwendlyn, 20, Ysabel, 18, and Truely, 11.

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Four years after Robyn, 43, entered the fold in 2010, Kody separated from Meri on paper to legally wed Robyn. Kody considers himself to be spiritually married to all women.

Christine announced on Instagram Tuesday she is leaving Kody. "After more than 25 years together, Kody and I have grown apart and I have made the difficult decision to leave," she said in a statement.

"We will continue to be a strong presence in each other's lives as we parent our beautiful children and support our wonderful family," she continued. "At this time, we ask for your grace and kindness as we navigate through this stage within our family."

Kody also issued a statement in support of Christine's choice.

"Christine's decision to leave comes with a great deal of sadness," he shared on Instagram. "We enjoyed many years together and I have a large amount of respect and admiration for her. Although we are moving forward on different paths, we will always remain committed parents."

Season 16 of Sister Wives premieres Sunday, Nov. 21 (10 p.m. ET), on TLC.