Hamlin, 19, and Disick, 37, have been spotted together on multiple occasions, and on Thanksgiving, Hamlin included Disick in an Instagram Story post about people she was "thankful" for. A source tells ET that his most recent ex, 22-year-old Sofia Richie -- whom he split from in June after three years together -- took a trip with her girlfriend to the Bahamas to get away from any drama.
"Sofia was a bit hurt that Scott was flaunting his relationship with Amelia Gray Hamlin so freely," the source says. "Scott has been preoccupied with Amelia and Scott is the type of guy who can't be alone and always needs someone there."
Meanwhile, the source says that 41-year-old Kourtney Kardashian -- whom he shares his three kids with, 10-year-old Mason, 8-year-old Penelope and 5-year-old Reign -- is unfazed.
"Kourtney isn't bothered that Scott is hanging out with Amelia Gray Hamlin and is so far past thinking about him in a romantic way," the source says. "She knows Scott better than anybody and she is supportive."
Last month, a source told ET that while Disick and Lisa Rinna's model daughter had been on a couple of dates, they weren't yet serious.
"[Disick] isn't actively looking for a relationship but is down for a good time," the source said.
According to the source, he was actually spending most of his time with Kardashian.
"Scott and Kourtney are together all the time, for the sake of the kids but also because they’re such good friends and get along so well," the source said. "Don't expect them to get back together though. They have a good thing going and it works perfectly for their family."