Following news that Moussa — who shares daughter Taylor Reese, 10, and son Brayden James, 5, with Haack — flipped out on the 38-year-old last week while filming their HGTV series, a source dished that Moussa regrets his reaction during their dispute.
The source confirmed that the coparents "did get into a disagreement" and Moussa, 39, "lashed out," but "he's super remorseful."
"They're exes who share a history and children and a workplace," the insider explained to PEOPLE, "but outside of coparenting, they're not friends."
OK! previously reported that the real estate agent lost his cool on Wednesday, July 14, over the way Haack signaled to him that she and the crew were ready to film the next segment. During the heated incident, Moussa reportedly told Haack that he enjoys watching her fail and insisted that he "made" her.
Adding fuel to the fire, Moussa compared his ex to fiancée Heather Rae Young, calling Haack a "washed-up loser." Continuing on with his rant, Moussa bragged about his life, allegedly yelling: "Look at me, look at me, look at me. It’s called winning," before concluding by screaming at Haack: "The world knows you're crazy!"
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The former flames wed in 2009 and found fame when they launched their Flip or Flop series in 2013. Despite calling it quits in 2016, Moussa and Haack continued to film their show — which is now shooting its tenth season — together.
The upcoming season reportedly follows their complicated lives as coparents and business partners. And while they managed to continue their working relationship after their 2018 divorce, sources dished that their recent dispute wasn't the first time the executive producers had a falling out on set.
In fact, there have reportedly been times where the two had to stop filming together and shoot segments separately just to keep production running smoothly.
Things on set may be tense, but Moussa and Haack's lives at home appear to be anything but stressful. Haack has been on cloud nine with new boyfriend Joshua Hall after her split from second husband Ant Anstead — who shares 22-month-old son Hudson London with the Christina on the Coast star.
She recently praised her new man on Instagram following her dispute with Moussa, calling Hall her "Ride or Die."
Meanwhile, Moussa is enjoying life with his soon-to-be wife, 33, as the lovebirds are currently on a relaxing trip in St. Barts.
Moussa made it clear that work and drama are the last things on his mind after the exes' alleged altercation, telling his Instagram followers that he and the Selling Sunset star are "off on vacation and have 10 days to just relax and be with each other — no work or interruptions, I think I can get used to this."