“Are you dating one person?” she asks in E! News‘ preview of Sunday’s episode. “Are you going steady?”
“I guess that’s what the kids are calling it,” Disick says.
“Is it Sofia?” Jenner asks, which Disick confirms. “Wait, so how old is she? Because I really don’t know. Is she Kylie’s age? 20?”
“19,” Disick admits, adding that he’s 34.
But Jenner, 62, acknowledges that she and late ex-husband Robert Kardashian also began as a May-December romance. “I was 17 and Robert was … well, 12 years older,” she says.
“You were underage, she’s not,” Disick points out.
“Touché!” Jenner says, smiling.
Only time will tell how the rest of the family — longtime friends of the Richies — will react. The mother of Disick’s three children, Kourtney Kardashian, is happily dating 24-year-old Younes Bendjima, which caused tension between the exes earlier this season on KUWTK.
And last month, her sister Kendall Jenner shaded the couple on Instagram when she left a comment on a photo shared by a fan account of Disick riding in a car with Richie, sons Reign Aston, 3, and Mason Dash, 8, and daughter Penelope Scotland, 5½.
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“Awww Scott and his kids,” the model wrote, adding a laughing face emoji.
A source told PEOPLE in November that Disick and Richie — who were first photographed cuddling at Cannes in May but have been dating since September — are “very serious” and that the daughter of Lionel Richie has been a positive influence on Disick, who has openly struggled with alcohol abuse.
“She’s been great for him,” the source said. “She’s made a big impact on his life and hasn’t partied at all since they met.”
Keeping Up With the Kardashians airs Sunday at 9 p.m. ET on E!