A source tells PEOPLE that the exes — who dated on and off for nine years before they split in 2015 and share three children together — are nothing but friendly.
“Kourtney and Scott have never been better!” the source says. “They’re both in happy relationships. They get on so well and co-parent so successfully.”
Kardashian turned 39 on Wednesday, a milestone she celebrated with a romantic night off the grid in an airstream with 24-year-old boyfriend Younes Bendjima, lunch with her three kids (sons Mason, 8, Reign, 3, and daughter Penelope, 5) in Malibu and an at-home dinner party with pals, momager Kris Jenner and sisters Kim Kardashian West and Kendall Jenner.
Disick, 34, has been seeing Sofia Richie, 19. They were first link when they were photographed cuddling aboard a yacht in Cannes in May 2017, and by September, the couple was inseparable.
In February, her famous dad, singer Lionel Richie, opened up about the surprising pairing.
“Is it going to be for life? I don’t know. But for right now it’s just a phase, and I’m going to stand real still in the corner, get me a good drink and not make too much noise,” he joked an interview with The Daily Telegraph.
But Sofia has been spending time with Kardashian and Disick’s children, suggesting the romance really is serious.
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“The initial reaction from Kourtney when she found out that Scott was dating Sofia was not positive,” an insider told PEOPLE in February. “Like most people, she thinks Sofia is way too young for him and doesn’t get it.”
Still, “he has very much shaped up in the past few months,” the insider said. “Kourtney is happy Scott is doing better.”