Kourtney Kardashian can’t deal with her first baby growing up. 

While on a trip to Australia with her husband Travis Barker, as well as the couple’s baby Rocky and Kourtney’s kids Penelope, 12, and Reign, 9—whom she shares with ex Scott Disick—the Kardashians star detailed why her eldest son, Mason, 14, decided to stay behind in California.

“Mason is home with his dad,” Kourtney explained in a confessional of the Kardashians’ July 18 episode. “Which makes me really sad, but I’m making the most of every second.”

Of course, the Poosh founder managed to enjoy her time with her younger kids during the trip to Sydney, which coincided with Travis’ band Blink-182’s tour to Australia. 

“We’re having the best time,” Kourtney added. “Because I was on bed rest before and then having a newborn at home, I haven’t really had any outings with my other kids.”

And while Kourtney—whose blended family also includes Travis’ kids Landon, 20, Alabama, 18, as well as stepdaughter Atiana De La Hoya, 25, whom he shares with ex Shanna Moakler—was missing her son, Scott has previously gushed over his growing bond with the couple’s teenager. 

“He's great,” Scott said of Mason during the season five premiere of the family’s reality series. “He's really been unbelievable. “We're closer than ever.”

Still, as he grows up, the 14-year-old continues to pull on his mother’s heartstrings. After graduating from middle school in May, Mason also officially joined Instagram—prompting his mom to note on his first post, “My first baby is on Insta, and I am not ok.”

But Mason isn’t the only one of Kourtney’s kids who is making her—and Kardashians fans—feel old. Penelope, for her part, just celebrated her 12th birthday with a beachside bash, complete with nine friends—including Kim Kardashian’s 11-year-old daughter North—night swims, and plenty of poolside snacks. 

As Kourtney wrote to Instagram July 16, showing off some moments from Penelope’s celebration, “3 days of casual, perfectly slowed down beach days to celebrate my little lady.”

Keep reading for more glimpses into Kourtney and Travis’ blended family life.

Kourtney Kardashian and Travis Barker was joined by Landon Barker—who he and ex Shanna Moakler share alongside daughter Alabama Barker and stepdaughter Atiana De La Hoya—at GQ's Men of the Year party in November 2022.

Kourtney and Travis took Alabama to Tommy Factory's New York Fashion Week show in September 2022.

Travis and Kourtney's son Rocky Barker made a cameo in his dad's photos from the Australia/New Zealand leg of Blink-182's world tour in March 2024.

Penelope Disick—who Kourtney and ex Scott Disick share alongside sons Mason Disick and Reign Disick—appeared with her mother in a vacation selfie from Australia.

Reign and Penelope enjoyed some fun in the sun during their family trip to Australia for Blink-182's tour.

Kourtney and Travis enjoyed some touristy activities in Australia.

In honor of Landon's 20th birthday in October 2023, Kourtney shared a throwback photo from 2017 of the then-teenager hanging out with Mason.

Alabama snaped a silly selfie with half-sister Atiana, as well as Kourtney and Penelope, during the Kardashians star's May 2022 wedding with Travis.

Kourtney took a break from her wedding festivities in to pose for a selfie with Alabama in May 2022.

Travis took Alabama, Landon and Atiana to the premiere of The Kardashians in April 2022. Meanwhile, Kourtney was joined by Reign.

Kourtney's oldest son Mason tagged along with Alabama and Atiana to Travis and Kourtney's front row outing at the AMIRI fashion show in February 2022.

Kourtney shared a close up of this sweet throwback of Alabama and Penelope for Alabama's 17th birthday.

Kourtney, Travis, Alabama, Atiana, Landon and Reign posed at Disneyland in April 2022. 

The group spent the day at the Happiest Place on Earth in honor of Kourtney's 43rd birthday.

Landon, Atiana and Kourtney bonded over a fun snapshot.

Penelope the artist! Travis shared her drawing of him in March 2022.

On Christmas Eve 2021, the Kardashian-Jenners joined the Barkers for a night of celebrations.

Travis and Penelope enjoy a game of checkers, while Kourtney and matriarch MJ Houghton watch the pair.

For Alabama's 16th birthday in December 2021, Kourtney and Travis surprised her with balloons that spelled out "BAMA 16."

Travis wrote in caption, "I LOVE YOU SO MUCH!!!"

Travis appeared with Kourtney and Penelope in a TikTok video posted on the mom-and-daughter duo's joint account.

"So happy for you guys," Travis' daughter Alabama wrote on a photo celebrating the couple's engagement. "I love u both!"

Landon joined his dad and Kourtney for some Halloween 2021 fun at Knott's Scary Farm in Southern California.

Kourtney recruited her son Mason for a trip to Universal Studios' Halloween Horror Nights with Travis and his daughter Alabama in 2022.

Atiana posed as the Bride of Frankenstein to Reign's Frankenstein during the spooky outing.

Kourtney's daughter Penelope rocked a devil costume as the crew headed to the Los Angeles immersive jack-o-lantern experience Nights of the Jack.

During their Nights of the Jack adventure, Alabama captured Travis and Penelope sharing a sweet moment as he walked around carrying her on his shoulders.

Even before they were dating, Travis and Kourtney were friends for years. Just look at this throwback photo of Mason, Landon, Alabama and Penelope from 2017.

Talk about a sweet birthday present! Travis gifted Kourtney's daughter Penelope a state-of-the-art drum set when she turned nine back in July 2021.

What better place to spend the Fourth of July 2021 than Disneyland? The happy couple celebrated the holiday there with Landon, Alabama and Reign.

Atiana opted to twin with Kourtney in matching snow gear during their first family trip together in Deer Valley, Utah, in April 2021.

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