"In fact, it's the hardest and most rewarding job that I have ever had," she tweeted of being a mom

Kourtney Kardashian is speaking out after her sisters, Kim Kardashian West and Khloé Kardashian, accused her of not having a strong work ethic on a recent episode of Keeping Up with the Kardashians.

The reality star, 40, defended herself against the accusations in a series of tweets on Thursday ahead of the second part of the season 18 premiere, writing on Twitter, “I won’t be live tweeting #KUWTK tonight, as I’m spending time with my kids while they are on spring break.”

“I realize that a lot of the conversation right now surrounds my work ethic, and I feel like I need to just make one thing clear: raising children is a job as well,” she wrote. “In fact, it’s the hardest and most rewarding job that I have ever had. I’ve decided to put my focus on my kids and my lifestyle brand, Poosh, which is all about finding YOUR healthy balance for living your best life.”

She continued, “I don’t judge anyone who chooses a different route, and I hope that everyone can appreciate my choices as well.”

Kourtney Kardashian Instagram
Kourtney Kardashian and daughter Penelope
| Credit: Kourtney Kardashian Instagram

Kourtney is mom to daughter Penelope Scotland, 7, and sons Mason Dash, 10, and Reign Aston, 5, with whom she shares with ex Scott Disick.

During the season 18 premiere of KUWTK, Kourtney and her sister Kim, 39, got into an aggressive altercation over long-simmering tensions about the Poosh creator’s boundaries when it comes to filming their reality show. After Kim accused her sister of not having a strong work ethic, the fight escalated.

Earlier this week, Kim admitted that their argument got “pretty intense” and the two had to take a break from filming after the fight.

“I feel like it’s been a lot of built-up resentment from Kourtney, or just feeling like she doesn’t really want to film anymore,” the SKIMS founder told Jimmy Fallon via video chat for an episode of The Tonight Show: At Home Edition on Monday.

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“We shut down production for a week after that,” Kim said. “I think everyone was really shook for a minute and just was like, ‘This isn’t our type of show. We want everyone to be comfortable and safe.’”

In a confessional on Thursday’s episode of KUWTK, Kourtney said she hit her boiling point during the argument.

“I don’t understand why there’s all this judgment about the way we each want to live our lives. We should be accepted for what we each want to do. It’s not a positive environment for me to want to be in every day when I feel like they’re so critical of me,” she said. “Every day I’m coming in, I’m like, ‘Why am I choosing to be in this environment?’ And I think I just reached my point of not being able to tolerate it anymore.”

Kourtney Kardashian slaps Kim

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The episode left off with Kourtney announcing that it was time to pull back from the reality show for the sake of her relationships with her family.

“I feel like I’m on this hamster wheel and it’s just not something I can continue to do,” she said. “I think some big changes need to happen.”

“I’ve decided to take a big step back from filming and really just pick and choose what I will allow cameras to follow.”