On Sunday evening, the couple — who have been officially dating since last September — left Nobu restaurant in Malibu, California, after dining together. Kardashian departed the L.A. hotspot in a separate vehicle, according to photos obtained by RadarOnline.
A source tells PEOPLE Kardashian “doesn’t necessarily care to get to know Sofia better, but she feels she needs to because of the kids.”
“Sofia spends time with Kourtney’s kids, so Kourtney wants to make sure they are all on the same page,” says the source. “Scott and Sofia tend to get into arguments. Kourtney wants to make sure the kids are in a positive environment when they are at Scott’s house. She is setting up rules for how things needs to be when the kids are with Scott.”
A second source tells PEOPLE Kardashian arrived by herself, while Disick and Richie, 20, arrived together.
“It was a quick dinner,” says the source. “It seemed a bit tense. It wasn’t like they are all friends and were hanging out for fun. It looked more like a business dinner.”
“It helps that Kourtney now trusts Sofia,” a source told PEOPLE in May. “The kids are allowed to spend time with her. Sofia likes having them and helps Scott. So far, the kids are giving Kourtney good reports about Sofia.”
The source added, “Sofia has shown over and over again that she is willing to stay with Scott even when things are not great — but Scott is doing well lately.”
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Her famous family agrees.
“Everyone really likes her. They think she’s a great influence and Scott is so in love, so it’s not a problem,” an insider close to the Kardashians told PEOPLE in September.
Richie hasn’t said much publicly about their relationship, though she opened up for a rare interview in September.
“We are very happy, very lovey dovey,” the daughter of singer Lionel Richie told Australian newspaper the Sydney Morning Herald’s The Goss. “We are best friends and that is mainly the strongest connection we have. We have always had that best friend connection and from there it has really worked out. I am so happy.”
Richie said that while “it’s hard to fully avoid” tabloid speculation, she doesn’t waste her time and energy on it.
“Everything is so false. I don’t read it because I just get really angry,” she said.