It has been one week since Kourtney Kardashian and Scott Disick welcomed their third child together, and on Sunday (Dec 21st) the reality TV couple revealed to the world what their new baby boy's name.

Kardashian
The happy couple have named their new baby boy Reign Aston Disick

The eldest Kardashian sister took to Instagram to share an adorable photograph of herself holding the tiny hand of the proud parents' newborn, with the caption, "Madly in love with my little Reign Aston Disick."

Kourtney, who have been with Scott for seven years, gave birth on the fifth birthday of their oldest son, Mason, on December 14th. They are also parents to a daughter, Penelope, who is 2-years-old.

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"The family is freaking out with joy," a source close to the pair told E!News at the time. "What an amazing coincidence."

While still heavily pregnant, Kourtney graced the December-January cover of FitPregnancy, and revealed she is quite the hands-on mother. "I'm not getting a baby nurse," she told the mag. "I take two months off and no one is allowed to bother me or talk to me about anything work-related-or maybe three months this time."

And although none of her pregnancies have been fairly easy, the oldest Kardashian sister absolutely loves being pregnant.

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"I love being pregnant in general," she said. "This time I'm more tired than I was the other times. I think it's because I'm always running around and working on different things. But I feel comfortable with how I look and feel. I find a pregnant body to be beautiful and an incredible reminder of what a woman's body is made to do."