TrickyD / Fame Flynet 1 / 14
TrickyD / Fame Flynet 1 / 14

After baring it all for DuJour magazine, Kourtney Kardashian finally caved and revealed the sex of her third child on Sunday's "Kourtney & Khloe Take the Hamptons."

And it looks like Penelope and Mason will be welcoming a baby brother!

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On the show, Kim Kardashian shares a video of the moment Kourtney finds out she's having a boy -- due later this month -- and we hear the excited screams that come from the mom-to-be.

Per usual, Mason steals the episode, saying, "I wanted a girl." Aunt Khloe Kardashian assures him that a little brother is better as he can "boss him around."

Mason's mom, however, is ecstatic about the sex. "I am so happy we're having a boy," Kourtney says. "It's going to be perfect for our family."

RELATED: Kourtney Kardashian Nude and Pregnant for 'DuJour' Magazine

There might be another pregnant Kardashian sister coming soon. Kim recently revealed to ET that she and Kanye West are trying for baby No. 2! "You know I kind of wish I was pregnant at the same time Kourtney is," she said back in August. "She's like more than half way in, so you know, we're trying."


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