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Kourtney Kardashian has two cute reasons to celebrate!
Both of her adorable boys, Mason Disick and Reign Disick, share a birthday on this special December day, so it's obviously time to party!
Kourtney and Scott Disick's firstborn son turns 6 today—seriously, where has the time gone?! And if that's not big enough, their youngest baby rings in his milestone first birthday!
In honor of the exciting occasion, take a peek at all of their sweetest pics, including some with sis Penelope Disick!
Watch Keeping Up With the Kardashians Sunday at 9 p.m., only on E!