Keeping calm with Kendall. Kim Kardashian seems baffled with sister Kendall Jenner’s sleep paralysis issue in a preview clip of the Sunday, November 6, episode of Keeping Up With the Kardashians.

In the clip, Jenner, 21, looks exhausted as she yawns and tells Kardashian, 36, that she’s been having trouble sleeping.

“This stupid sleep paralysis thing is, like, really getting to me,” the model tells her older sister, explaining that the issue happens when “you’re asleep and then in the middle of the night, basically your mind wakes up but your body’s still asleep.”

Kardashian’s eyes widen as Jenner continues to explain the eerie condition. “It’s the scariest thing in the entire world. … You can’t do anything, [and] you’re freaking out,” Jenner says. “All you want to be able to do is move, so you’re laying there, trying to move, trying to relax.”

Kardashian looks stunned as she asks, “And you can’t communicate it?” Later, in a confessional clip, she tells the cameras that she “feels so bad” that her younger sister is going through the troubling phase at all.

“I mean, I thought I was having anxiety,” the Selfish author says. “This is so much scarier. I’ve never heard of sleep paralysis, and I think it sounds like such a crazy experience.”

Kardashian attended Jenner’s 21st birthday bash earlier this week, on Wednesday, November 2, one of her first public appearances since the horrifying Paris robbery incident last month.

“Kim was there in a sweater, in a great mood, and gushing to everyone about how amazing [husband] Kanye West’s [Saint Pablo] show is and how she loves going to his concerts,” an insider exclusively tells Us. “She seemed in totally great spirits, very social and smiling with everyone.”

Keeping Up With the Kardashians airs on E! Sundays at 9 p.m. ET.

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