Los Angeles, Dec 15 (AHN) Kourtney Kardashian Barker and Scott Disick's sons marked their joint birthdays on Sunday. While Mason turned 16, Reign is 11 now.

Grandma Kris Jenner paid a special birthday tribute to her "amazing grandsons" by sharing some old photos of Mason and Reign over the years on her IG.

In a heartfelt birthday note, Kris thanked Reign for bringing "so much joy, laughter and light wherever you go", whereas she described Mason as "a kind, thoughtful, creative, and confident young man".

Her birthday note read, "Happy birthday to our birthday twins, my amazing grandsons, Mason and Reign! Mason, I can’t believe you are 16!!! Watching you grow into such a kind, thoughtful, creative, and confident young man has been one of the greatest joys of my life and I’m so proud of you. Reign, you bring so much joy, laughter, and light wherever you go. Your curiosity, energy, and spirit fill every room and remind us all to see the world with wonder. You both have your own unique magic and you make our family so proud just by being who you are. I feel endlessly grateful and blessed to be your grandma and I love you both more than words can say!! Love Lovey xoxo (sic)."

Kourtney commemorated the occasion by sharing a heartfelt post on her Instagram Stories. Uploading a throwback pic of the birthday boys, she wrote, "My birthday boys!! Two of the greatest loves of my life (sic)."

On the other hand, Disick reshared grandma Kris Jenner's birthday post for Mason and Reign on his Instagram Stories, along with the text, "Happy birthday my boys! You make my life better each and every day! (sic)."

For those who do not know, Kourtney also has a daughter, Penelope, with Disick, who was born in July 2012. Additionally, she is also a mom to son Rocky, whom she had with husband Travis Barker.