This means war! Kourtney Kardashian and Scott Disick were at it yet again at her Calabasas, CA home in late October. The two got into a “huge fight,” a source tells In Touch exclusively, because Scott wants to introduce his new girlfriend, 19-year-old model Sofia Richie, to Mason, 7, Penelope, 5, and Reign, 2, the three kids he shares with Kourtney. His ex, however, isn’t having it.

“Scott and Kourtney were at each other’s throats,” says the source. “The argument got so heated that Scott stormed out of Kourtney’s house, slamming the door behind him.” The former couple clearly doesn’t see eye to eye. The hard-partying lothario, 34, who’s had a long line of flings since splitting from Kourtney two years ago, insists Sofia is “the one.”

scott disick sofia richie getty

(Photo Credit: Getty Images)

But Kourtney, who dismissed his dalliances as “not dating, just, like, boning” on a recent episode of Keeping Up With the Kardashians doesn’t believe Sofia, Scott’s girlfriend since the summer, is stepmom material. Kourtney, 38, “thinks Sofia is too young to be a good role model,” says the source. “She insists that Scott has to be in a serious relationship for at least six months before introducing a girlfriend to the children.”

Scott is particularly steamed because he thinks Kourtney is a hypocrite. The Pretty Little Thing
clothing designer has been seeing 24-year-old model Younes Bendjima — 14 years Kourtney’s junior — for less than a year. “Younes met the kids months ago!” the source notes. “Scott can’t stand Younes and isn’t particularly happy about him spending time with the children, but Kourtney still goes ahead and does whatever she wants without taking Scott’s feelings into consideration. He’s livid about Kourtney’s double standards.”

Scott also believes Kourtney resents Sofia because of who she is. She’s the daughter of music legend Lionel Richie and sister of Kim’s friend Nicole Richie. “He’s convinced Kourtney is jealous that she’s been replaced by a hot, younger model, who also comes from a famous family,” says the source. “Kourtney also secretly feels betrayed by Sofia, as she’s known the Kardashians for years and yet still pursued Scott. Kourt feels like Sofia has stabbed her in the back.”

No matter how upset Kourtney is, Scott is determined to integrate Sofia into his family. “Sofia is
the first woman Scott has been serious about since Kourtney,” says the source. “The kids mean everything to him, and he’ll do whatever it takes to make Sofia a part of their lives.”

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