After Kourtney held her ground on picking a time to shoot their family Christmas card, Kim called her "the least exciting to look at" -- pushing her older sister to the breaking point. Kourtney breaks down in an emotional phone call to Khloe, who just so happens to be sitting with Kim and their mom, Kris Jenner.
"I'm not here to be mistreated by my f**king b**ch family," she cries. "Kim saying that I'm the least interesting to look at -- who even speaks like that?"
"You guys just have really different values than me. I choose to be a mother to my three kids. I am not here looking for another job. I already work enough, more than I would like to," Kourtney continues, as Kim gets out of her chair.
"You don't do f**king sh*t!" Kim yells, causing Khloe to get up and walk away, with Kim following her.
"You would honestly think that we have more jobs, so work around our schedule," Kim yells. "You do whatever the f**k you want to do and you don't do sh*t, so be accommodating to the people who actually do sh*t."
That's when Kourtney takes it to the next level, calling Kim a "very distraught, evil human being." "I'm not going to live my life around people that make me not feel good on a daily basis," she says.
"Well, clearly you're going through something else, because you're acting like a f**king lunatic. So maybe deal with that," Kim shouts back, forcing Khloe and Kris to take Kourtney's side.
"Oh my god, Kimberly. That's not OK to say," Khloe interrupts.
"What I said was rude and I wasn't even being serious. I said I'm sorry for that, but you're the most entitled f**king person on the planet when you work the least," Kim continues.
But the fight isn't over! Watch below.
Keeping Up With the Kardashians airs Sundays at 9 p.m. ET/PT on E!