Kourtney Kardashian in tears over son Mason for this heartbreaking reason

Kourtney Kardashian admitted to a fan over the weekend that she and sister Kylie Jenner had been on FaceTime – and ended up in tears while discussing the star's oldest son Mason, ten. The pair had both been talking about Mason as he celebrated his birthday on Saturday, and got nostalgic as they reflected on just how quickly the time had gone since he had been born. Kourtney had paid tribute to her first-born on Instagram, and in the comments, one of the fans had written: "Cannot believe he is ten. Time really does fly by," to which the doting mum replied: "@kyliejenner and I just cried together over FaceTime."

Kourtney Kardashian was in tears as she reflected on son Mason growing older

It wasn't just Mason who was celebrating his birthday on Saturday, but his younger brother Reign too. Born five years apart, the brothers share a special bond, and many members of their family paid tribute to the pair on their big day. Kourtney posted a photo of Mason in the back of the car during a sunset ride, and wrote: "Happiest tenth birthday to the boy who changed my heart forever. No one is cooler or sweeter than you." For Reign, Kourtney shared a series of pictures of the pair pulling faces together and wrote : "My silly baby is 5 years old today. Life has so much more meaning with this wild, sensitive boy who has shown me the world through such different eyes."

Mason had many birthday tributes from his famous family on his special day

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Mason and Reign's aunt Kim Kardashian also paid touching tributes to her nephews on her Instagram page. Reflecting on Mason's milestone year, she posted a picture of herself holding him as a newborn baby, and wrote: "Happy Birthday Mason! You are so special and bring such a light into all of our lives! I know it’s annoying all of the other cousins are so much younger but they look up to you so much! Thank you for being the best big cousin for my babies. I can’t believe you were this photo was taken 10 years ago! We all love you so much." The mother-of-four then posted a picture of herself kissing Reign, writing: "Happy Birthday Reigny! You are the silliest little kid I know. Thank you for being Saint's best friend and always having his back! I love you more than you could ever imagine!!!!"

Mason's younger brother Reign also celebrated his fifth birthday

The siblings' dad Scott was next to post on social media, choosing a picture of himself and Mason, and writing in the caption: "It’s just me and my best friend. 10 years of the best love ever." The doting dad also shared a photo of Reign enjoying a giant ice lolly and wrote: "My little reign maker turns 5 today! Nothing better than this."

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Grandmother Kris Jenner posted a joint tribute to her two grandsons, sharing a collection of photos of them both over the years, and writing: "Happy birthday to my precious grandsons Mason and Reign! You are the greatest blessings, and we love you so much. Mason, I can’t believe you are 10 today! You are growing into the funniest, smartest, most loving and amazing little man and I’m so proud of you! And Reign, 5 today, and the coolest kid in the world. It brings me so much joy to watch you both grow together as amazing brothers, sons, grandsons and cousins. I love you both to the moon and back. Xo."

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