Kourtney Kardashian is ''proud'' of her relationship with Scott Disick and his girlfriend Sofia Richie.

The 40-year-old reality star has three children - Mason, nine, Penelope, six, and Reign, four - with her former partner, and has said she's pleased she still has a civil relationship with Scott, and even gets on well with his new girlfriend Sofia.

The trio recently vacationed together with Scott and Kourtney's kids, and although Kourtney doesn't think they'll make a habit of going on trips together, she ''loves'' that she gets invited.

Speaking to Paper magazine, she said: ''[Our relationship is] probably the thing I'm most proud of. I don't think we'll go on every trip together, but I love that I'm invited.''

Kourtney and Scott's newfound friendship comes after they recently admitted they found it ''challenging'' to co-parent their tots when they first split in 2015, and especially after they each found love in new relationships.

Kourtney - who began dating Younes Bendjima in 2016 until she split from him last year - said: ''I think the hardest part was when we both started new relationships. That caused fights between you and I - about introducing the kids [to our new partners]. I think that caused the most challenges.''

To which Scott - who has been romancing 20-year-old Sofia since 2017 - added: ''It's one of those things you don't think is ever going to happen, but like everything in the world, you know, things move [on].''

The 'Keeping Up with the Kardashians' stars also admitted to having been to therapy together to learn to ''communicate'' better.

Kourtney revealed: ''I think that was like the time that you and I ... literally had to go to therapy to talk, to even be able to like, communicate together.''

And Scott, 35, says they've now learned what's ''appropriate'' to talk about with each other, and they're in a ''really good place'' as co-parents.

He said: ''I think the biggest challenge was just trying to figure out how we separate ... our relationship as friends and parents and still be on the same page and what is, I guess, appropriate and what's not and when to be able to talk to each other.

''In the beginning, I think you set good [boundaries,] and then we learned from that and we've gotten to a really good place.''