Scott Disick Celebrates Son Mason, 14, Graduating From Middle School With New Photo: 'Congratulations to My Best Friend in the World'

Time flies!

On Thursday, June 6, Scott Disick announced that his and ex Kourtney Kardashian 's eldest child, Mason Disick , graduated from middle school.

"Congratulations 2 my best friend in the world 🌎 for graduatiuating [sic] middle school and now on to high school!" Scott, 41, captioned an Instagram photo of himself, the 14-year-old and his friend at Nobu for a celebratory dinner. "Let’s go mart!!"

Fans were shocked that Mason was so mature , with one person commenting on the snap, "How is he in high school already? I swear he was just born 😢."

"Go Mase!!! It’s crazy how fast they grow up 😭," echoed another supporter.

It looks like Mason's sister, Penelope , 11, joined them for the meal, as Scott was in the same outfit when he uploaded a picture with her to his Instagram Story that day.

The dad-of-three also shares son Reign , 9, with Kourtney, 45.

While the teenager used to be very private and refrained from appearing on the family's reality shows as he got older, he seems to have come out of his shell, launching a public Instagram profile last month.

After posting his first photo on the social media app, his aunt Khloé Kardashian , 39, commented, "I can’t believe this is happening."

"You’re really on Instagram," noted Kim Kardashian , 43, while his mom wrote, "My first baby."

Though the Talentless founder and Kourtney were closer before she started dating now-husband Travis Barker , 48, an insider told a news outlet that the exes are "cordial" coparents.

"She is focused on her own life and just wants their kids to feel happy and loved," the source explained. "Kourtney is not concerning herself too much with the details of her ex's life , though, as she is focused solely on her four children and her marriage with Travis — which she is intent on prioritizing."

However, the Poosh founder did chime in when Scott started losing too much weight from reportedly using Mounjaro .

Though the New York native now seems to be in better shape, his gaunt appearance earlier this year sparked concerns.

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"Kourtney has been worried about him — she does when it pertains to their kids. She wants to see Scott as healthy as possible. Her kids need a father," the source said at the time. "She's not had many major heart-to-hearts with him, but she has sent some tough love to Scott to help him improve."

Scott appeared to take everyone's words to heart and allegedly hired a nutritionist to get back on track.