"Actually, I was in Mexico and I got a call from Heidi saying, 'Call me right now,' " Kardashian tells MTV News. "So I called her and she had said to me, 'What do you think? What's your opinion on if I were to do Playboy?'"
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Kardashian's advice? "Go for it."
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"I think that now's the time," she says. "I think it's a very classy magazine. It's artsy. I talked her through the whole process and helped her make up her mind."
Kardashian also said Spencer Pratt also weighed in.
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"Her and Spencer talked it over," Kardashian tells MTV. "They felt like it was the right thing for her to do and I'm anxious to see it."