This Sunday, on Keeping Up with the Kardashians, Kim Kardashian West and her sister Kourtney Kardashian get in a huge blowout fight. The famous sisters debrief the fight where Kim calls her sister a “fake humanitarian hoe.”

Since the sisters became known after the first episode aired in 2007, the Kardashian clan has been entertaining the reality TV masses for over a decade. Fans have watched as these two sisters be best friends one minute to the most brutal arguments the next minute. Kourtney and Kim have butted heads a lot over the years over everything from parenting to fashion. There is, of course, the iconic moment when Kim was crying after she lost her diamond earring in the ocean while on a family vacation and Kourtney mocked her because she’s crying over something so ridiculous while, “people are dying” in the world.

In the newest episode, both sisters are recounting their sides of a heated argument. It starts with Kourtney in a car on the phone with her friend, Sarah, about what went down. She says, “Kim and I just got in the biggest fight.” She says Kim went crazy on her and is “sending me the meanest text messages.” According to Kourtney, Kim called her, “The biggest ungrateful b*tch,” after she felt Kourtney was ungrateful for her help when she “intervened when your stylist pulled the nastiest clothes for you for your birthday party.” Kourtney’s car stops and picks up Khloé where she explains what a “joke” the fight between her and Kim has become.

Kim explained her side of the story to their mom, Kris Jenner, explaining, “Basically, I just got into the biggest fight with Kourtney today.” Kim explains why she thinks he sister is a “btch, like on another level” after when she tried to help her pick out the right outfit for her birthday party, Kourtney said that she didn’t want her help because she doesn’t like her style. In which Kourtney reminded her that Kim is going to school to become a lawyer, asking her if she has anything better to worry about. That’s when Kim went off of Kourtney by saying how she “all of a sudden” becomes a humanitarian even though she thinks she hasn’t “contributed one ounce to the world.” And then proceeds to call Kourtney a “fcking fake humanitarian hoe.” Kris sits there with her mouth wide open as Kim explains what she called Kourtney.

Viewers are watching Keeping Up with the Kardashians with the hope that they can see an iconic sister fight and this week was not a letdown. Fans can watch and see if the relationship between the two sisters will remain strong together or if they continue to fight like they did this week. So far this is the worst insult fans have heard between the sisters, but it likely won’t be the last.

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Keeping Up with the Kardashians airs Sundays at 9 pm EST on E!.