Soon Mason and Penelope Disick will have a little brother. Kourtney Kardashian announced on Sunday's installment of her reality-TV series Kourtney and Khloe Take the Hamptons that she and partner Scott Disick are adding another son to their growing brood. First-born Mason turns 5 on December 14 and his younger sister Penelope is 2.

The eldest Kardashian sister, 35, is due to give birth within the next few weeks.

"I am so happy that we're having a boy," said Kourtney, via E! News. "It's going to be perfect for our family."

As for Mason? His initial reaction was one of disappointment.

"I wanted a girl," he confessed on camera, to which aunt Khloe Kardashian replied: "Girls don't like aliens and Lego guys. When you have a brother you can say, 'Look at all my Lego guys, brother.' You get to be rough and you can boss him around because you're the older one."

Kourtney and Scott photographed in August

Compared with her sisters, Kourtney is known as the (relatively quieter) earth mama with a taste for organic food — she had Mason eating kale chips as a toddler. But at 9 months pregnant, she pulled a Kim and posed in the buff for the pages of DuJour.

"To me, nudity is not something to be ashamed of," she said. "I'm not embarrassed of my body. I'm at my best when I'm pregnant. It's such an amazing feeling, the transformation that your body goes through. There's something about that that's so empowering and beautiful and I just really embrace it."

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