Mason Disick and Reign Disick are celebrating their birthday on the same day! Mason was born on Dec. 14 in 2009 and Reign was born five years later on the same day, bonding these two brothers forever. This year, Mason is turning 11 while Reign is turning five, and we can’t believe how quickly these two are growing up! Not only was Mason was the very first KarJenner kid, but their family has grown so much over the past decade that he now has nine cousins.