Kourtney Kardashian and Scott Disick Talk Going to Therapy for Co-Parenting When Dating Others

Kourtney Kardashian and Scott Disick take their parenting duties very seriously.

In a new video for her lifestyle brand Poosh, posted Monday, the Keeping Up with the Kardashians star and her ex sat down to talk about how they harmoniously co-parent their three kids together: Reign Aston, 4, Penelope Scotland, 6½, and Mason Dash, 9.

One secret to their success? Therapy sessions that the exes began attending together when Disick, 35, began seeing girlfriend Sofia Richie.

“I think the hardest part [of co-parenting] was when we both started new relationships,” said Kardashian, 40, who previously dated Younes Bendjima before they split this past August. ” ‘Cause that caused fights between you and I about introducing the kids.”

“It’s one of those things you don’t think is ever gonna happen,” agreed Disick.

“We had to literally go to therapy to talk … to even get through … to be able to communicate together,” Kardashian recalled.

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RELATED: Kourtney Kardashian Wants to Show “Positive” Co-Parenting with Scott Disick on KUWTK

The former couple’s disagreements were chronicled during KUWTK last season, when Kardashian tearfully confided in sister Kim Kardashian West after hearing Disick had introduced their kids to Richie, 20, without her consent.

“I think it’s just more of a principle thing — that they made this rule and they’ve been going to this co-parenting therapy together,” said Kardashian West, 38. “I definitely want to be there to support Kourtney and Scott, but it’s just kind of their thing and I don’t get involved.”

Disick, meanwhile, sought advice from Kris Jenner and told her they had agreed to hold off on the introduction until after the holidays — so technically, his timing was legitimate.

“Last night when we got home, the kids were there, so of course they met my girlfriend,” he told Jenner, 63. “Kourtney goes, ‘You’re a f—ing joke. … You don’t care. We discussed with the therapist that we were going to wait.’ I said, ‘We discussed with the therapist that we were going to wait until after the new year and after the holiday!’ ”