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Kourtney Kardashian isn't the only one who's pleased with her 44-pound weight loss.

In the Jan. 14 issue of Us Weekly, the 33-year-old E! reality star shows off her slim post-baby body in a series of sexy bikini shots; The unretouched pictures were taken in Miami on Dec. 13.

PHOTOS: How Kourtney Kardashian got her beach-ready body

"It was harder to lose weight the second time around," admits Kardashian, mom to son Mason, 3, and daughter Penelope, 6 months (with partner Scott Disick, 29). "I gained 45 pounds with Penelope."

PHOTOS: Hollywood's hottest post-baby bodies

The 5-foot star, now 106 pounds, feels sexier than ever -- and Disick agrees. "He likes me any way," Kardashian tells Us. "But I think his favorite is when I'm skinnier."

Together since 2006, the proud parents are still not sold on the idea of marriage. "We're just so busy with everything going on, and we feel good where we are," Kardashian explains. After Penelope's July 2012 arrival, the pair plan to wait before trying for a third child.

PHOTOS: Introducing Penelope Scotland Disick!

Says Kardashian, "I think we're still adjusting to what life looks like with two!"

For exclusive details on how Kardashian got her post-baby body back -- including her favorite healthy snacks and dance-focused workouts -- pick up the new issue of Us Weekly, out now!


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