The 34-year-old "Keeping Up with the Kardashians" star and 19-year-old model dined with Jonathan Cheban and another pal mid-flight Monday after appearing to confirm dating reports during a trip to Miami.
"Family dinner 40k feet above the rest," Disick captioned a photo of the meal on Instagram Stories. He also posted a picture of himself resting his legs on Richie's lap.
Disick and Richie were spotted kissing at a celebratory dinner Saturday in Miami after making their relationship Instagram official.
The pair shared a smooch before enjoying a dessert reading "Congratulations."
Disick and Richie were seen holding hands the next day while out to lunch at Delano, according to People.
The pair avoided paparazzi while shopping Tuesday in Calabasas, Calif., following their return to Los Angeles from Miami.
Disick shares three children with ex-partner Kourtney Kardashian, from whom he split in 2015 after nine years of dating.
Sources told Us Weekly Kardashian isn't fazed by Disick's romance with Richie, the daughter of singer Lionel Richie.
"Kourtney thinks this fling with Sofia is a little weird, but nothing shocks her anymore. She shares three kids with him, so she'll always want the best for him and will always make sure he's happy."
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