Kourtney Kardashian Kourtney Kardashian

Meet Reign!

Kourtney Kardashian posted the first public pic of her third child, Reign Aston, to Instagram on Thursday. (In the Kardashian klan, you don't really exist until you've been Instagrammed.)

Kourtney Kardashian posts backstage photo with breast pump

"My little turtle dove angel baby boy Reign Aston Disick," she captioned the pic.

My little turtle dove angel baby boy Reign Aston Disick.

A photo posted by Kourtney Kardashian (@kourtneykardash) on

Reign joined older brother Mason, 5, and sister Penelope, 2, late last year. Reign was born on Mason's 5th birthday — Dec.14. Parents Kourtney Kardashian and Scott Disick have been together since 2006.

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