An Instagram user named Adam posted photos of the apparently content threesome eating at a Mexican restaurant called Edith's, in Cabo, just days before Christmas.
Kourt and Scott's oldest son Mason was also sitting at the table.
"Keeping up with @kourtneykardash and @letthelordbewithyou in Cabo San Lucas," the Instagram fan wrote.
Scott, 39, sat in the middle with Sofia, 20, leaning over and staring at Kourt, 39, in one of the surprising photos of the scene at the brightly decorated Mexican restaurant.
Kourtney appeared to be having a great time, smiling in another picture and then in yet another snap, speaking to Mason as Scott and Sofia chatted.
The Instagram user also posted a short video of the three, and in it, Kourtney is seen showing Sofia something on her cell phone like she's a close friend!
But the truce isn't news to RadarOnline.com readers, as we previously reported that Kourtney had softened towards her baby daddy's young galpal.
As RadarOnline.com exclusively learned, Kourtney invited model Sofia to Mason and other son Reign's birthday parties this month.
"Kourtney decided to let it go and is not stopping Sofia from coming to celebrate her boys' birthdays," a source told RadarOnline.com. "The two of them are finally cool, for the most part!"
Mexico has been a popular vacation spot for the Kardashians and also Scott and Sofia.
Kourt and Scott have spent a lot of time together recently, stirring reconciliation rumors for the parents.
But it appears now that she's accepted his girlfriend instead!
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