Rob Kardashian: My Sisters Are 'Great' Role Models

Oprah with the Kardashian/Jenner family -- Facebook

Rob Kardashian is a lot tougher on his sisters' looks than most.

When asked by Oprah Winfrey for her "Oprah's Next Chapter" Kardashian family interview if they would have been successful if they were "not good looking kids," Rob offered a response that took his siblings by surprise.

PLAY IT NOW: Oprah Takes On The Kardashians

"They're not skinny women," he told Oprah, in a clip from the interview, posted on E!. "They're not models here."

"You are so sweet," a seemingly annoyed Khloe Kardashian chimed in.

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"I am just saying you're great role models for women, young girls," he added.

After reflecting on Oprah's question, Khloe suggested the family might not have been so successful if they were less stunning.

"To be honest, probably not. You have to have this bombshell over here -- [Kim], and this petite little bundle of joy-- [Kourtney], and this hunk, next to me, [Rob]," Khloe told Oprah.

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Kim suggested that their curves and Armenian heritage also helped make the family famous.

"I don't think it would have happened if we were all like, skinny, pretty models. I think it has to do with us, the curves, the dark hair," Kim told Oprah. "I think it was a combination of -- I remember when the wave of Jennifer Lopez and Salma Hayek and these beautiful Hispanic women came to light and I looked up to them and I loved them, but then I was like, 'Where are like Middle Eastern women?' I think we kind of helped that category or helped broaden that... People just have it. I can't explain what it is."

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In another clip, released to Access Hollywood on Thursday, Oprah can be seen asking if the Kardashian children feel their mom, Kris Jenner, who is also their manager, is "pimping" them out.

"I think that's so ridiculous because first of all, we'd have to hire a manager," Kim said to Oprah's "pimping" question.

"She's our mom," Rob stated.

"Regardless, someone is going to get that [cut of our income]," Kim continued. "No one will fight harder for you than your own mother. She knows us, she knows all of our moods... We just get each other, we vibe, it works."

"Oprah's Next Chapter" airs Sunday at 9/8c on OWN.

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