In a new clip that dropped on Thursday, the tense argument that led up to 40-year-old Kourtney calling 39-year-old Kim a "c**t" and Kim punching and kicking her in return is revealed. It all starts when Kim and 24-year-old Kendall Jenner have a conversation about work ethic, and Kim implies that she and 35-year-old Khloe Kardashian work harder than Kendall and Kourtney.
"The problem is, if I was on my death bed, I would still show up," Kim tells Kendall. "Mom is so used to me and Kourtney -- eh, Khloe -- going on our death beds."
"Are you f**king kidding me?" Kendall retorts. "Like, I literally will come at you right now. I swear to God. ... I've been sick as f**k, having major panic attacks. I work my f**king a** off when I'm sick or not."
But as Kendall and Kim's conversation gets heated, Kourtney -- who's been sitting with Khloe nearby -- jumps in. Kourtney has been at odds with the rest of her family in recent years about no longer wanting to be on their reality show.
"But you act like I don't do sh**," Kourtney tells Kim. "You have this narrative in your mind. ... I will literally f**k you up if you mention it again. Literally shut the f**k up and don't laugh like that. You look like a freak."
Kourtney explains to KUWTK cameras that she's fed up with Kim constantly saying she has a stronger work ethic than her.
"It's such bulls**t," she says. "We don't all have to do things the same way."
Kourtney and Kim's fight eventually turns physical when Kourtney throws an object at Kim.
"But if I wanted to be a stay-at-home mom, then that's f**king fine, you f**king literal c**t," Kourtney tells her.
As for Kim's side of the story, she explains to KUWTK cameras that their mom, Kris Jenner, is so used to her and Khloe always following through with their commitments, unlike their other siblings. She references their youngest sister, 22-year-old Kylie Jenner, canceling an appearance at Paris Fashion Week in September because she was sick.