The spark between Scott Disick and Sofia Richie could also be burning out.
“Scott and Sofia’s relationship is starting to fizzle,” a supply tells PEOPLE. “They’re starting to argue more, and it’s bothering Sofia.”
“She thought he would be more serious about their relationship and is finding herself to be more frustrated with him as time goes on,” the supply continues. “Everything everyone has been telling her to look out for, she’s now starting to see for herself. It’s really upsetting for her, but she is trying to work through it.”
Disick, 34, and Richie, 19, had been pictured cuddling up aboard a yacht within the south of France through the Cannes Film Festival in May. At the time, Richie — who beforehand dated Justin Bieber — adamantly denied something romantic was occurring, tweeting that the 2 had been “simply homies.”
But in mid-September, a supply advised PEOPLE they’d turn out to be “inseparable,” and so they confirmed their romance through social media later that month, packing on the PDA throughout a visit to Mexico.
An insider beforehand advised PEOPLE that Richie is “much more invested in the relationship” than Disick, who shares three children together with his ex Kourtney Kardashian, 38.
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On the opposite hand, the supply says Kardashian’s relationship together with her 24-year-old boyfriend Younes Bendjima is “definitely getting more serious.”
“Kourtney loves the attention Younes gives her, and she thinks he is super attractive. They definitely have an intense physical connection. She loves his swagger and his intensity with her,” the supply provides.
Last week, one other supply additionally advised PEOPLE that issues between the couple — who’ve been courting since early May — are heating up, and that he’s even invited to mother Kris Jenner‘s annual vacation celebration.
“He makes her very happy,” the supply continued. “He is spending more time with her family and everyone likes him.”
The supply mentioned that though Bendjima hasn’t met Kardashian’s three children — Mason, 7, Penelope, 5, and Reign, 2 — “it seems like it’s just a matter of time before Kourtney is ready to introduce him.”