Khloe Kardashian snaps at Kourtney Kardashian

In a newly released sneak peek, Khloé and Kim are anxiously awaiting their older sister’s arrival for a meeting — and the tensions are already simmering.

“I don’t understand [her] f—ing attitude,” says Khloé, 34, while Kim, 37, admits she’s “so afraid” of Kourtney, 39.

When Kourtney finally arrives, she immediately starts tapping at her phone, ignoring the conversation going on around her. Meanwhile, Kim is discussing the cherry blossom-themed baby shower she threw in November ahead of daughter Chicago‘s arrival.

“I really wasn’t going to plan a baby shower, but I think it’s important for North so she starts feeling that it’s coming,” she explains.

Khloé offers to help and turns expectantly to Kourtney, who changes the subject entirely.

“Who let you choose black covers for your furniture?” she asks Khloé. “Disgusting. Usually people get a colour that’s like, neutral to your floor. Who chooses black?”

“That’s nice, Kourtney. Thanks for coming over, thanks for being so lovely,” says Khloé. “When I come into your house, I’ll make sure to say just a critical comment.”

They start bickering back and forth and Khloé eventually loses her cool.

“What is up your a—?” she demands. “Seriously, what the f— is wrong with you? Why are you so bitchy these days? You’re just mean.”

Later, Khloé — then pregnant with daughter True — says Kourtney can’t possibly be unaware of her attitude problem.

“It confuses me how Kourtney is confused that we’re butting heads,” she says. “Trust me — if I wasn’t pregnant, I probably would have drowned you in the f—ing pool.”

This article originally appeared on PEOPLE.