Kourtney Kardashian's got no problems with her ex dating someone else, because if he's happy ... she's happy. Besides ... she's clearly moved on.
Our Kardashian sources tell us ... Scott Disick's relationship with 19-year-old Sofia Richie doesn't bother Kourtney, because she thinks it's genuine and feels good that he's moving on. She's clearly done the same, also with someone much younger -- 24-year-old model Younes Bendjima.
We're told Kourtney and Scott have been on good terms for months now and have the co-parenting thing down ... and Scott being with Sofia hasn't rocked the boat.
As we reported ... Kourtney laid out the rules for Scott -- he had to clean up his act if he wanted to be around their kids. So far, it seems like his time with Sofia is helping.