Kourtney Kardashian had a lot to celebrate this weekend. The Lemme founder paid her sons Mason and Reign a touching and nostalgic birthday celebration. And if you haven’t been keeping up with the Kardashians, no, they’re not twins. The brothers — whom Kardashian shares with her ex Scott Disick along with 12-year-old daughter Penelope — simply share the same birthday.

Mason Disick was born on December 14, 2009 and Reign was born five years later – on December 14, 2014.

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“My birthday girls,” Kourtney captioned her Instagram post. “So special to me it hurts my heart.”

Kourtney – who also shares one-year-old son Rocky with husband Travis Barker – then shared throwback photos of her boys. The carousel featured a priceless opening shot of Mason giving his little brother a piggyback ride as they watch the fireworks in the distance.

“I still can’t believe they were born on the same day ❤️❤️❤️,” Khloé Kardashian commented, racking up more than 4.5 thousand likes. Even 10 years later, the Kardashian family and their followers are still embarrassed by the incredibly special coincidence. Same birthday?! Five years apart?! This is incredible.

Birthday tribute queen Kris Jenner also posted a tribute to her grandchildren with a similar sentiment.

“Our birthday twins! “I still can’t believe you both have the exact same birthday,” the Kardashian matriarch wrote. “What a special blessing that binds you forever…You fill my life with so much pride and happiness, and I love you both with every part of my heart and soul.”

“I am so proud of the incredible boys you are and look forward to the amazing future you both have ahead of you! 🥰❤️🎂🎉”

To celebrate his eldest’s birthday, Disick gifted Mason a mini version of the Mercedes-Benz G-Class station wagon. “This has to be the coolest little car I’ve ever seen! You deserve every inch of it! I love you more than anything in life,” the father of three wrote on his Instagram Story, subtly throwing shade at his other children, just like twice-retired NFL quarterback Tom Brady recently did.

Not only is this an extremely lavish gift, but it’s also one that Mason won’t be able to legally use for another six months, when he gets his driver’s license. And then – as the self-proclaimed “Lord Disick” said – it’s time to “let the good times roll.”

Before you head out, check out these celebrity parents’ stories about how they teach their teens to drive.

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