Tensions are brewing betweenKendall JennerandKourtney Kardashianthis week onKeeping Up with the Kardashians.

In a sneak peek at Sunday’s episode, Kendall sits down withKhloé Kardashianto rant about their older sister after she tagged along on a ski trip to Mammoth, California, with Kendall’s friends in January.

“You know, Kourtney and I have been getting a bit closer over the past couple of years and I love that she hangs out with me and my friends,” says Kendall, 23. “But to be honest, I felt like there were just some moments where she was a bit rude and it really started to get to me at a certain point.”

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Kendall Jenner and Kourtney Kardashian

Kendall recounts to Khloé that at one point during the trip, Kourtney, 40, put her feet up on the center console in Kendall’s car.

“Mind you, it’s like, rainy and muddy outside,” she explains. “I go, ‘Kourt, can you not put your feet up on my thing?’ And she goes, ‘Kendall, it’s a f—ing vehicle.’ I go, ‘So? I don’t want your shoes all over my car.’ And she goes and puts her feet onto the [headrests].”

“That’s so rude,” says Khloé, 34.

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Another example? Kendall recalls that later in the trip, Kourtney made fun of her after she asked one of their friends, Fai Khadra, to keep her car keys on him while they went skiing.

“I was like, ‘Are you sure you have a zip pocket? I don’t want it to fall out.’ … I mean, literally, how would we get home if we lost the key?” Kendall says. “And Kourtney goes, ‘Kendall, chill the f— out, it’s a key.’ And then my friends, all of them laugh with her. None of them took my side, they’re all just laughing together. And then she feels that validation.”

“I’m not blaming my friends at all,” she adds. “They’re not doing it because they’re trying to be mean.”

“You’re not mad at them — you’re more mad that she even puts you in that situation,” Khloé says.

“Right,” Kendall acknowledges. “She was like, putting me down to make herself feel higher or cooler.”

“That’s just so weird,” Khloé says.

Later, Khloé admits she’s “so annoyed” with Kourtney.

“She’s supposed to be the older sister, but it just seems like Kourtney was bullying Kendall the entire time,” she says. “I mean, that’s so lame for anyone to do that.”

Keeping Up with the Kardashiansairs Sundays (9 p.m. ET) on E!

source: people.com