'Sister Wives' star Janelle Brown demands the cameras stop filming her after cursing out Kody during the explosive fight that led to their split

• "Sister Wives" season 18 has been chronicling the unraveling of Kody and Janelle Brown's relationship.
• On Sunday's episode, Kody and Janelle have an explosive fight that appears to mark the end of their marriage.

On the latest episode of TLC's "Sister Wives," Janelle Brown curses out then-husband Kody during an intense fight that leads to their split.

During an August 2023 People interview ahead of the season 18 premiere, Janelle referred to an explosive argument in December 2021 as the point when she knew she needed to separate from Kody. "This burden came off me, and I thought, 'Wow. Okay, it's over,'" she told People of the incident.

Viewers got to see that fight unfold on Sunday's episode. In the scene, which TLC confirmed to Insider was filmed in December 2021, Kody visits Janelle's rental apartment in downtown Flagstaff, Arizona to discuss their separate holiday plans. Spending the holidays apart had been a sore subject for the couple for many months.

As seen throughout season 17, Kody had said Gabriel and Garrison, his adult sons with Janelle, couldn't visit the home he shared with his legal wife, Robyn Brown, until they apologized for disrespecting his strict COVID-19 rules. It was a major point of contention with Janelle, who has six children with Kody ranging in age from 18 to 29.

Caught between her sons and her husband, Janelle decides to rent a house with her former sister wife Christine Brown so their children can spend Christmas together. Kody eventually backtracks on his demand, saying that the boys are welcome to spend the holiday with him if they are willing to have an open conversation about their tension with him. But by the time he makes up his mind, it's too late to make amends or change plans, which leads to the big fight.

On Sunday's episode, Kody and Janelle's argument begins because Kody tells his then-wife that it's her responsibility to help him communicate with his sons and uphold his rules.

"All you have to do is support what I'm doing. Do you understand that parents are supposed to make a united front?" he asks Janelle at one point, referring to the fact that she didn't make her adult children abide by any COVID-19 rules outside of CDC guidelines.

During the argument, he also cites Janelle's "lack of loyalty," "lack of trust," and "gaslighting" as reasons why their relationship is strained. When Janelle accuses Kody of being manipulative as the argument heats up, he points to the camera and dares her to "tell the whole world" how he's being manipulative, in a rare moment of breaking the fourth wall.

Kody then compares himself to the Greek God Atlas, "carrying this family on my shoulders." He says that as soon as he took that burden off, his family fell apart.

In response, Janelle calls Kody out for "pushing me out the door" by giving her an ultimatum between him and her kids. She believes Kody is trying to get her to leave him so he can be monogamous with Robyn, his only legal wife, without having to take any blame for leaving his other wives.

The breaking point of the argument comes when Janelle gets so mad at Kody for cutting her off while she's speaking that she says "shut your fucking mouth and let me talk for a minute."

It's Kody who leaves Janelle's house after telling her that she cheated him out of a relationship with his family. He says he doesn't expect to see their children for Christmas or to have any support from her when it comes to being their parents.

He then refuses Janelle's demand that he stay and talk to her. "Fuck you," she says as Kody slams the door behind him.

Alone in her apartment, a visibly angry and shaken Janelle then tells a cameraman off-screen to "shut it off" and the screen goes dark.

While Janelle and Kody were never legally married, the two were in a spiritual marriage for over 26 years before they decided to officially split. That conversation is expected to be shown later in season 18.

"Sister Wives" airs Sundays at 10 p.m ET on TLC.