In an exclusive sneak peek at Sunday's episode, the longtime couple gets into an argument about Janelle's failure to be "loyal" to Kody.
The spat stems from Kody's belief that "there's this unwillingness from some members of the family to accept other members of the family." In this case, he's referencing how some family members take issue with Kody's fourth wife Robyn Brown.
"I have somebody in my life who is fundamentally loyal to me who sees me as the head of the family," Kody, 53, says while referencing Robyn, 44, without naming her. "I'm saying to you that you and I get that if you're loyal to me."
As he drives his point further, Kody clarifies that he's not saying Janelle, 53, needs to behave exactly like Robyn.
"I'm telling Janelle to just be loyal," he tells the cameras. "I have 100 percent loyalty from Robyn. So, okay, yeah, I guess that's like Robyn. Nope. I'm just asking for loyalty. I'm asking to be the head of my household."
Janelle, on the other hand, has long "suspected" that Kody has felt this way.
"I'm not going to be this person. I'm not going to become Robyn," she says in a separate confessional. "It frustrates me beyond belief that he perceives this one wife, this one relationship [as] she's so perfect, she's such a saint, she was so nice to us and she was treated so wrong. So everybody better apologize for being mean to her or else this isn't going to work anymore. This is the subtext I've been hearing this whole damn day."
Janelle adds, "Kody's been a broken record about this for the last little bit, how Robyn's been so victimized. She was so sweet to everybody. She put herself out there. I don't perceive it that way. I perceive that we were plural families trying to figure it out. And she always kind of kept herself a little separate."
Continuing to speak to Kody about the matter, Janelle questions if her husband would be "acting this defensive" about her if the "situation was reversed."
"You and I've been acting like we weren't a married couple for most of our marriage, Janelle," he says in response. "I don't know why it's been OK for so many years, and it's not now, but you actually live like a single woman."
Gabe Ginsberg/FilmMagic Janelle and Kody Brown
The Brown family's TLC series has shown the ups and downs of navigating plural marriage. In this current season, Kody's issues with Christine, 50, as well as Janelle have been a focal point.
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Sister Wives airs Sundays at 10 p.m. ET on TLC.