The group's outing came just after Kylie Jenner and Travis Scott's Disney family adventure.
Kardashian, 42, and Barker, 45, were spotted on the King Arthur Carrousel together, leaning close as the Blink-182 drummer showed his girlfriend something on his phone. The Keeping Up With the Kardashians star, dressed in a Mickey Mouse sweatshirt, paired her look with a black mask and light pants.
All three of Kardashian's kids with ex Scott Disick -- 11-year-old Mason, 8-year-old Penelope and 6-year-old Reign -- came along for the outing, as did Barker's kids with ex Shanna Moakler -- 17-year-old Landon and 15-year-old Alabama. Moakler's oldest child, 22-year-old Atiana De La Hoya, also accompanied the group.
Kardashian and Barker's Disneyland adventure came just one day after Kylie Jenner hit the park with Travis Scott and Kim Kardashian West.
Jenner corralled several of the family's youngest members -- including 3-year-old daughter Stormi, and cousins Chicago West, 3, and Dream Kardashian, 4 -- for the afternoon out.
A source told ET earlier this month that Jenner and Scott were "having fun together" amid their on-off romance. "They've always had a strong connection and chemistry and they're exploring their relationship romantically again," the source shared.
As for Barker and Kardashian, a source said the pair has been talking about engagement and marriage.
"Travis would absolutely love to tie the knot with Kourtney, but Kourtney hasn't been sure that's the step she wants to take in their relationship right now," the source said. "She is extraordinarily happy and doesn't feel the need or want the pressure of getting married."
The source added, "There are a lot of other factors that concern her if they were to take their relationship to that next level, one of them being Scott [Disick] and more importantly, her kids and what that adjustment would mean for them."
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