Kourtney Kardashian Says She’s Happy She ‘Retired Into Motherhood’ After SKIMS Shoot: ‘Not That Girl Anymore’ 

Kourtney Kardashian Barker is happy to be living a quieter life these days.

In a new episode of The Kardashians, the mom of four, 45, transformed into a model for the day on set with sister Kim Kardashian for their dual photo shoot. The sisters were dressed in leopard-print pieces from SKIMS collaboration with Dolce & Gabbana.

In a confessional, Kardashian Barker explains that the day was fun, but it was also, "A good reminder of why I retired into motherhood."

"I mean it’s fun to be on set with Kim and the vibes are immaculate, but I think this makes me want to wear massive clothes. I’m not into showing my body right now," she candidly shares.

"I don’t work out, it’s not my priority. I’m in a taking care of my baby and kids and going on tour with my husband mode. I’m just not that girl anymore.”

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During another scene, Kardashian Barker admits that the long day is trying her patience, especially because she's breastfeeding on demand.

"When I get hangry when I’m breastfeeding, I will complain about anything and everything that’s in my way," she says.

In the background of the scene, 15-month-old son Rocky can be heard crying as Kardashian Barker tries to find out the timing for the next time she's needed in front of the camera.

When someone remarks that they're surprised Kardashian Barker had Rocky there, she tells the member of her team, “I couldn’t be away from him for this long.”

Kardashian Barker and husband Travis Barker prioritize time with their blended family. The reality star and the Blink-182 drummer each three children from previous relationships, in addition to Rocky. Kardashian Barker shares Mason, 15, Penelope and Reign, 10, with her ex Scott Disick, while Barker is father to his son Landon, 21, daughter Alabama, 19, and stepdaughter Atiana, 25, all of whom he shares with ex-wife Shanna Moakler. 

In an exclusive interview with PEOPLE after his Run Travis Run 5K in New Orleans, the Blink 182 drummer recently revealed that Rocky is already starting to drum and that he's playing the instrument "constantly, 24/7." Barker said that as his children continue to grow, he hopes he and his wife can "just lead by example," as they develop.

"I hope we just lead by example," Barker told PEOPLE. "I mean [Rocky], he just turned 15 months today, and he's like already playing drums and guitar and everything, so I feel like all we can do is steer them."

"I think you're born with like this DNA of who you are, but, like, we could always be there to just, you know, lead them in the right direction," he added, sharing that he also plays guitar.

New episodes of The Kardashians premiere Thursdays on Hulu.