Secret struggle. Scott Disick was the perfect image of a doting dad. Over the long Thanksgiving weekend, he spent some seriously adorable father-son time with his and ex Kourtney Kardashian’s eldest child, Mason, 7, taking him to NYC to visit the Intrepid Sea, Air & Space Museum before hopping a private jet bound for Miami, where they took a helicopter ride and hit the beach. Scott’s also often been on daddy-daughter dates with Penelope, 5.

But he’s rarely seen out with his youngest child, son Reign. “This sounds horrible to say, but Scott is closest to Mason and then Penelope,” an insider exclusively tells In Touch, adding that though Scott, 34, has a bond with Reign, who turns three on Dec. 14, “it’s not the same as the one he had with Mason when he was that young.”

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DAY 3 : my little drummer boy 25 DAYS OF CHRISTMAS

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Now a source has some bombshell insight into why that might be. “Reign was conceived when Kourtney and Scott were going through a rough patch. At the time, Scott didn’t question whether he was the father, but that soon changed,” explains the source. “It didn’t take long for Scott to start having doubts as to whether Reign is actually his child.”

Scott’s fears were stoked any time people commented on his kids’ looks. “What really got under Scott’s skin is when family members said that Reign didn’t look like him,” says the insider. “Penelope and Mason are dead ringers for Scott, but Reign looks more like Kourtney.”

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sand in our shoes

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And her volatile relationship with Scott is legendary. “There were countless times when they’d split up and not see each other for weeks. And whenever they had a huge argument,” says the source, Kourtney, 38, “went out of her way to seek revenge. She’d often party with her pals and close guy friends.” (They finally broke up for good in 2015, when Reign was about six months old. At the time, a Lord Disick insider told In Touch Scott hadn’t spent time with Reign “for months.”)

Scott — who is in a relationship with Sofia Richie, the 19-year-old sister of Kardashian family friend Nicole Richie — eventually questioned Kourtney about Reign’s parentage. “She outright denied [that Reign could be someone else’s],” says the source. “During the heated bust-up, Scott brought up doing a DNA test. Kourtney said no, which has only heightened his suspicions.”

Another insider also says that Kourtney, who is currently dating 24-year-old model Younes Bendjima, isn’t interested in debating with Scott: “Kourtney didn’t want to hear it when Scott asked if he’s really the father.”

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