According to the insider, the two exes are getting along great and Kardashian “seems very happy” with Disick.
The source also says Kardashian has expressed that she would love to have another baby, and another insider confirms to PEOPLE that the star “definitely wants four kids.”
Though Kardashian, 37, and Disick, 33, ended their nine-year relationship last July, they have remained committed to co-parenting their three kids: Mason, 6, Penelope, 4, and Reign, who will turn 2 in December.
In recent months, the Keeping Up with the Kardashians stars have been spending plenty of time together with the kids. Disick has often spent the night at Kardashian’s house to be with the children, though according to the source, they are now officially living together as a family again.
The former couple spent last weekend in Cabo San Lucas, Mexico, with their kids. At the time, a source told PEOPLE Disick “set it all up” in an attempt to “try and make things work again with Kourtney.”
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“He surprised her and whisked her away on this trip,” said the insider, while another source added the two “seem very close and happy.”
Most recently, Kardashian spoke publicly about the relationship during an interview with Cosmopolitan for her October cover story.
“The idea of having my family together is amazing, but it’s not the way things ended up. They may end up there. I’m not sure,” she said. “To me, it’s in God’s hands. If it’s meant to be, then things will line up.”
“We definitely tried for a long time. But relationships are exhausting!” she added. “Being able to focus on the kids and me right now is good. We say to each other all the time, ‘I’m the coolest ex-girlfriend/baby mama you could ever ask for!’ “
Keeping Up with the Kardashians airs Sundays (9 p.m. ET) on E!