Kris Jenner Celebrates Grandsons Reign, 8, and Mason, 13, on the Brothers' Shared Birthday

Kris Jenner is celebrating a special day for not one, but two of her grandkids.

In an Instagram post on Wednesday, the momager paid tribute to both of Kourtney Kardashian's boys — Reign, 8, and Mason, 13 — as they both celebrate their birthdays on Dec. 14.

"Happy birthday to two of the brightest lights in my life, my beautiful grandsons, Mason and Reign!" she wrote.

In a sweet message to her now-teenage grandson, the grandma of twelve wrote, "Mason, you are my first-born grandson, and I am so very proud of you each and every day! You've grown into such an amazing young man, and I adore you."

"Reign, you are the funniest!!!! You are one special guy with so many facets to your personality!!!" she added.

"Both of you have the most amazing qualities and are kind, considerate, loving, so smart, so talented in so many ways, and such a special magical part of our family … AND it's wild that you were born on the very same day!!!! Five years apart!!!!"

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"You are both the best sons, grandsons, brothers, nephews, and friends to all of us and I love you so much!!!!!!! Lovey xoxo 😍🥰🥳🎂🙏," she concluded.

Kardashian shares her sons and daughter Penelope, 10, with ex Scott Disick.

Earlier this month, the 67-year-old shared a video on her Instagram Story of a large group of "Elf on a Shelf" figures situated on a staircase in her home. A closer look showed that the elves represent each of her grandchildren, with a "Lovey" elf in the middle of the group of twelve.

As the video panned, viewers could see four elves for Kim Kardashian's four children — Psalm, 3, Chicago, 4, Saint, 7, and North, 9 — on one side of Jenner's elf. On the other side, there were, elves for Khloé Kardashian's two children — True, 4, and 4-month-old "baby boy Thompson."

The row of elves in front of them featured a shuffle of Kourtney and Kylie Jenner's children, as well as Rob Kardashian's daughter, 6-year-old Dream.

From left to right sits Reign, Stormi, Dream, Penelope, Mason, and "baby boy Webster."

In scenes from a family dinner on the season finale of The Kardashians, Kourtney's blended family with husband Travis Barker gathered together for dinner.

"Our family's expanding and growing and we have so much to be thankful for," the Lemme founder, explained in a confessional spliced with scenes of them all at the table.

Kourtney continued, "I love the idea of a blended family. I think that the more kids, the merrier. You have all these siblings and more people to love. It's a beautiful thing."