Kourtney Kardashian Pregnant With 3rd Child

June 8, 2014 — -- Kourtney Kardashian and Scott Disick are expecting their third child.

"I am pregnant," she said tonight in a preview for this season of "Keeping Up with the Kardashians." Then she added, "This was not a plan."

Kardashian, 35, and Disick, 31, are already parents to Mason, 4, and Penelope, who turns 2 in July. The two have been dating for eight years and met in 2007.

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Currently Kardashian and her sister, Khloe Kardashian, are in the Hamptons filming a spin-off show. There's no word how the pregnancy will fit into the show.

"She's really excited but she's nervous too," a source told People magazine of the pregnancy news. "Three kids is a lot to handle! But she's happy -- she's always wanted a big family with Scott."

Kardashian may be nervous, but she's said in the past that being a mother comes naturally.

"Both Mason and Penelope still sleep in my bed," Kardashian told Redbook for its April issue, on newsstands now. "It's what came naturally to me; I didn't plan it."

She added, "I think once you become a mom, your instincts kick in, so far as what to do and how to handle everything."

This news came just weeks after Kardashian's sister, Kim Kardashian, married rapper Kanye West in one of the most talked-about weddings of the year. The couple tied the knot in Florence, Italy, after having a pre-wedding bash in Paris.