Kim Kardashian: Sis Kourtney “Not That Nurturing” Before Her Pregnancy

 Courtesy of Rachel Ray

Like all new mothers, Kourtney Kardashian has a lot to learn when she gives birth to her first child — a boy — sometime this month.

In fact, her sister Kim Kardashian was initially surprised that Kourtney was becoming a mom at all. "Kourtney was never ever the type that I ever would think would ever want to have kids," say Kim, 29, during an appearance on Thursday's The Rachael Ray Show. "She owns a kid's clothing store, and if a kid would come in she would be like, 'Where's your mom? You need to go find your mom and come in with her.' She didn't understand it and she wasn't that nurturing." But her expectant sister has "just completely changed" during her pregnancy, Kim says.

Khloe Kardashian, appearing alongside Kim for Ray's show, adds that Kourtney assumed that she'd be breast feeding for five years. "Kourtney was like 'I'm so excited, I don't have to cook for five years!'" Khloe, 25, tells Ray. "And I go 'what do you mean?' She's like, 'I'm gonna breast feed.' I go, 'For five years?' She has, like, no idea!"

The baby-to-be's father is Scott Disick, boyfriend to Kourtney, 30.

"She will be a good mother — she knows how to take care of someone," Disick, 26, recently told Us Weekly, adding that she'll also be "strict."

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