Mason Disick seemed to be following in his uncle Rob Kardashian's footsteps, staying out of the limelight, until last month saw the 14-year-old join Instagram.
Since his debut on the social media platform, Mason has been increasingly active, sharing glimpses into his charmed life, and on Thursday, his dad, Scott Disick gave an insight into their close father-son bond as he celebrated his and Kourtney Kardashian's son's big achievement.
Alongside a photo of himself, Mason and a friend, Scott wrote: "Congratulations to my best friend in the world for graduating middle school and now on to high school!"
Scott then appeared to share his private nickname for Mason, writing: "Let's go Mart!" as he signed off the post, which saw them posing outside celebrity hotspot Nobu.
Mason is fond of nicknames, and was the first one to call Khloe 'Koko', and Kim 'Kiki', when he was tiny.
With their penchant for pet names, it's no surprise that Mason isn't the only Kardashian kid with a cute nickname...
Kardashian nicknames
On Keeping Up With The Kardashians, Mason was regularly referred to as Mase by his parents and aunts Kim and Khloe Kardashian, so Mart is likely a private name his dad calls him.
© InstagramPenelope Disick's nicknames
Mason's younger sister, Penelope, 11, famously gets called P and Poosh by her mother, who even named her lifestyle brand after her daughter. Scott also recently shared a snap of his daughter referring to her as Peep – so cute!
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Reign Disick's nicknames
Scott and Kourtney's nine-year-old son is called Reigny by his mother, while Scott often calls him Rayman – cute!
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Kim Kardashian's kids' nicknames
North West, 10, is often called Northie, while her dad Kanye West regularly calls his firstborn Nori. Eight-year-old Saint goes by Sainty, while Chicago, six, is called Chi or Chi Chi, while the littlest sibling, Psalm, four, gets called Psalmye, to rhyme with Kanye, by his older sisters.
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Khloe Kardashian kids' nicknames
Khloe and Tristan Thompson's daughter, True, six, gets called TuTu by her family – so cute. Her baby brother, Tatum, who turns two this summer, is nickname-free, thus far!
© InstagramKylie Jenner's kids' nicknames
Kylie's daughter with Travis Scott, goes by Storm (although Stormi is already undeniably cute), while their son, Aire, two, took so long to be given his name, after initially being called Wolfe, we suspect he mainly goes by Aire!
© InstagramRob Kardashian's daughter's nickname
Little Dream Kardashian, seven, is the apple of her father's eye, and the family calls her Dreamy – which suits her well.
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