Kris Jenner Posts Instagram Birthday Tribute to Grandsons Reign, 10, and Mason, 15

Kris Jenner is sending out all the grandma love.

The Kardashians star, 69, dedicated a sweet Instagram posts full of recurring images to grandchildren Mason, 15, and Reign, 10, who share a December 14 birthday.

“Happy birthday to my two incredible grandsons, Mason and Reign!” she began her post about the boys, who are the sons of Jenner’s oldest daughter, Kourtney Kardashian, 45, and her ex Scott Disick, 41.

“Our birthday twins! I still can’t believe you two share the exact same birthday,” she continued. “What a special blessing that connects you forever. You are both so deeply loved and I am eternally grateful to God for choosing me to be your grandmother.”

Jenner then took a moment to reflect on each of the boys individually.

“Mason, you are so kind, creative, smart, talented and the best brother, son, grandson, cousin and friend,” the mother of six wrote. “Watching you grow up to be such a caring and wonderful young man is pure magic – you make us all so proud.”

“Reign, you bring so much energy, laughter and joy wherever you go,” she continued. “Your inquisitive mind and lively personality light up any room. You are smart, funny and full of so much love and I feel blessed to witness the amazing little person you are becoming. You fill my life with so much pride and happiness.”

“I love you both with all my heart and soul. I am so proud of the incredible boys you are and excited for the amazing future you both have ahead of you!” she finished her post.

The proud grandmother accompanied the sweet birthday message with a carousel of photos of her and her grandchildren at various ages.

Jenner – who has 13 grandchildren – recently shared that she fully embraces being “the underdog”.

“I just have to take a deep breath,” she told PEOPLE when discussing hosting her six children and their children for the upcoming holiday. “There are 13 of them! You can’t control that kind of chaos.”

“It’s so much fun,” she explained. “I’m just such a holiday girl. I mean, I’m just obsessed with celebrating every holiday.”

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The reality star matriarch also noted that her family always spends Christmas morning at her house and that they “go hard” on gifts. The self-proclaimed neat freak also revealed that – despite the chaos – she tries to keep things in order.

“I kind of walk around with paper towels and my all-purpose cleaner all the time,” she said. “I always did. The rest of the family, they’re used to me.”