There's officially a new member of the Kardashian family! Kourtney Kardashian and her longtime partner Scott Disick welcomed their third child together on Dec. 14. Now the new mom is giving fans a first look at the baby and finally revealing his name.

Yesterday (Dec. 21), the reality star shared a precious photo of the infant holding her hand, captioning the pic, "Madly in love with my little Reign Aston Disick." Awwww! We're literally melting.

Reign joins siblings five-year-old Mason Dash Disick and two-year-old Penelope Scotland Disick. (Fun fact: Reign was born on Mason's fifth birthday!)

Chances are we'll be seeing a lot more of Reign, courtesy of 'Keeping Up with the Kardashians' and its numerous spin-offs. His older siblings regularly appear on the E! shows (and might be our favorite cast-members!).

During her pregnancy, Kourtney made headlines by posing nude for the cover of DuJour magazine. She looked radiant, telling the magazine, "“To me, nudity is not something to be ashamed of. I’m not embarrassed of my body. I’m at my best when I’m pregnant.”

We're sending our best wished to Kourtney, Scott, Mason, Penelope and the rest of the Kardashians during this exciting time!

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