Scott Disick buys Son Mason a Mini Mercedes G-Wagon for his 15th birthday

Scott Disick is on his way out!

On Saturday, December 14, the reality star, 41, celebrated her son Mason Dash’s 15th birthday as well as son Reign Aston’s 10th birthday.

Posting snaps on his Instagram stories, Disick — who shares his sons and daughter Penelope Scotland, 12, with ex Kourtney Kardashian – revealed he gave one of his boys a mini Mercedes G-Wagon.

While the proud dad didn’t say which birthday boy he was giving the car to, he did mention that it was for his “big boy.”

“Happy birthday big boy! Felt it was only fair 4 you 2 get your first g wagon even if it’s a mini g wagon it’s still a wagon! Love u son!!!!!!,” Disick captioned his caption together with a picture of the black mini G-Wagon with a matching ribbon on top.

Never miss a story – sign up PEOPLE’s free daily newsletter to keep you updated on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.

The vehicle was also sitting next to other black cars in front of Disick’s home.

“Let the good times roll,” he wrote.

Sharing a photo of the back of the mini G-Wagon. Disick continued: “Happy birthday!!!! Mini g wagon g wagon g wagon.”

PEOPLE Puzzler crossword is here! How fast can you solve it? Play now!

“That has to be the coolest little buggy I’ve ever seen! You deserve every inch of it! Love you more than anything in life,” he added.

The father of three then shared a photo of himself attending a Los Angeles Chargers game with Reign and a friend.

“Had 2 a lot of fun with you at your first game you asked me to take you to and I don’t even like sports,” Disick’s caption read. “That’s when you know you really love your child! Just kidding love you more than life young blood, happy day son!”

Mason and Reigns’ mom also shared a sweet birthday tribute to them via a carousel that included photos of Mason carrying Reign on his back, plus throwback photos from their baby years.

“My birthday boys. So special to me it hurts my heart,” Kardashian captioned the photo.

Grandma Kris Jenner also shared a lengthy tribute in her birthday post to her grandchildren.

“Happy birthday to my two incredible grandsons, Mason and Reign! Our birthday twins! I still can’t believe you two share the exact same birthday,” she wrote. “What a special blessing that binds you together forever. You are both so deeply loved and I am eternally grateful to God for choosing me to be your grandmother.”