Kourtney Kardashian Strikes a Pose in Costa Rica With Daughter Penelope, Niece North

Kourtney Kardashian is once again proving that she and ex Scott Disick are owning the title of modern family.

Kardashian and Disick took their kids on a family vacation to Costa Rica and struck an adorable pose with her daughter Penelope — who will be seven next month — and niece, North West, 6.

All three rocked sunglasses as they appeared to be on a boat.

A source told PEOPLE that the 40-year-old Keeping Up With the Kardashians star and Disick were enjoying a family vacation with their three kids, Penelope, Mason, 9, and Reign, 4, when her sister Kim Kardashian and husband Kanye West decided to join with their three kids, North, Saint, 3, and Chicago, 17-months-old.

“They are all filming for the show [Keeping Up With the Kardashians],” the source revealed. “They have a lot of ocean and rainforest activities planned.”

Earlier in the week, Kardashian showed off a photo of herself laying on the beach rocking a one-piece, vintage Dior bikini.

This time around, Disick’s girlfriend Sofia Richie did not join the Kardashians on their family getaway, despite them doing so back in December when they went to Cabo together.

“Honestly, it was fine,” Kardashian said about all three of them on one vacation during a recent episode of Keeping Up With the Kardashians. “She’s like, easy to be around. She’s not causing drama.”

“The trip was really fun and easy. I know that we don’t have to travel together and I don’t think that we will take very trip together, but it was totally not awkward,” she continued. “I feel like we are doing our best to make everything super normal for the kids. I know with my parents, as soon as everyone got along, life was so much easier. So I think as long as we’re all okay with it, I think it’s really amazing to be able to travel together.”

Not long ago, Kardashian opened up about how she’s most proud of the fact that her relationship with Disick is in a healthy state and that she’s able to get along with his 20-year-old girlfriend. She also admitted that she’s flattered they invite her on trips together — although, she doesn’t foresee them all traveling as a family pack on every vacation, but says it feels nice to be included.