Kourtney, 37, who also shares 4-year-old daughter Penelope with Disick, 33, was the first to take to social media to send her love to Mason, who turned 7, and Reign, who turned 2.
“It is both of my baby boys birthdays today!!!” she gushed on Twitter.
The mother of three also shared a sweet post on her app in honor of her two sons. “How crazy is it that I have two boys born on the same exact day? It is truly so special and meant to be. They changed my heart forever. Happy birthday to the coolest brothers I know!!!” she wrote.
Grandmother Kris Jenner was next, taking to Instagram to share an adorable picture of the two brothers.
“Happy birthday to these two sweet boys!!” she wrote. “Our precious angels Mason and Reign. I love you more than words can say. #myheart.”
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Kris, 61, shared a second birthday message for the boys on her daughter Kim Kardashian West‘s website and app. (Kim, 36, has refrained from posting on her app or on social media since her traumatic robbery at gunpoint in Paris this past October, though her family members regularly take over to share their own content.)
“Happy birthday to my two sweet boys Mason and Reign who were miraculously born on the exact same day five years apart,” wrote Kris alongside several pictures of Kim cuddling with her two nephews over the years.
“You bring joy and happiness to me and everyone in our family and it is the greatest honor and gift in my life to watch you grow,” added Kris. “I love you!!! — Lovie.”
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Khloé Kardashian took to her app to wish both of her nephews a very happy birthday with a sweet message and accompanying photos. “Born to be besties!!! Happy birthday to the special boys who share the same birthday! God blessed you with a sibling soul mate and I’m so thrilled to be your auntie. Watching you grow up has been one of the greatest joys of my life!” Khloé, 32, penned.
“Happy birthday, Mason and Reign! I hope you both have the most amazing day!!!” she wrote. “I love that you two share a birthday — it feels like a really special day. It’s so fun to watch you both grow up right before my eyes. I love you both!”
Finally, uncle Rob Kardashian shared a throwback photo of himself kissing Mason as a toddler on Instagram. “HAPPY BIRTHDAY MASEEEEE AND REIGN! Can’t believe you guys were born on the same day! That’s wild! I love you both so much happy birthday!!!!” Kardashian, 29, captioned the picture.
Keep checking for more sweet birthday shoutouts throughout the day. Happy birthday, Mason and Reign!