The new season's first trailer shows Christine, 50, packing her life into boxes after deciding to leave her plural marriage. "I have decided to leave. I'm gonna leave Kody," Christine says in a confessional.
While acknowledging some of the tension between herself and Kody, Christine explains part of what caused her to leave. She notes that "to Kody, Robyn [Brown]'s more important."
"It's been heartbreaking being your wife for years," Christine tells Kody, 53, during an emotional conversation between the two.
"I agreed to be a sister wife," she later adds in a confessional. "But I agreed to be an equal wife."
In a meeting with the other wives, Kody is unable to hold back his frustration with Christine.
"You never tried to have a really good relationship with these people and that's the reason I'm pissed off," Kody yells at Christine as Robyn, 43, and Janelle Brown look on. "Man, just the knife in the kidneys over all these years."
Before storming off, Kody adds: "All the sacrifices that I've made to love you."
It soon becomes clear that Christine's absence majorly impacts the entire family. The trailer even teases how hard Christine's sister wives are taking the news.
For Janelle, Christine's departure was always in the cards. "I feel like it's more of an inevitability coming instead of a 'Let's try to work this out,'" Janelle, 53, said.
As Meri Brown addresses Christine's decision, she says through tears: "I felt like Christine was more than a sister wife. I felt like she was a friend for a lot of years."
But Janelle is also worried about the repercussions of Christine's departure. "I'm not really sure we have a family anymore," Janelle worries.
The Brown family women attempt to "rebuild" after the setback, but other issues glare at the forefront, including Janelle's shaking confidence in her own marriage to Kody. At one point, she tells the cameras that Kody is "no longer acting like my husband."
What still lies in store for the family is yet to be seen. "The message that we had to the world about functional polygamy seems so dysfunctional now," Kody says in a confessional.
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Christine announced her separation from Kody in November 2021. The longtime pair — who share six children together — had been together for 25 years.
The previous Sister Wives season heavily focused on Christine's unhappiness in the marriage, leading up to the twosome's eventual breakup. Their problems worsened when Kody said he was "not interested in having an intimate marriage" with Christine anymore.
Season 17 of Sister Wives premieres Sept. 11 at 10 p.m. ET on TLC.