The 'Keeping Up with the Kardashians' star flew from The Hamptons, where she is filming the E! spin-off show, to their home in Calabasas, California to host her niece's first birthday party with sister Kim Kardashian West.
A source told TMZ Kourtney decided not to let Scott attend but her actions backfired when he opted to stay in Southampton, New York to enjoy a belated birthday celebration for himself on Saturday (20.06.14), after turning 31 on May 26.
TMZ reports: ''Disick didn't stew over the snub - he had a belated birthday party at 1Oak [club] in The Hamptons where he sprayed champagne on fellow party-goers.''
The source claims Kourtney believed Scott would ''feel the burn'' for being left out because North's party was thrown in their backyard.
They added: ''The tension revolves around Scott's propensity for partying and leaving the family in the dust.
''Kourtney gave Scott's plane ticket to a nanny ... again, a not-so-subtle insult that seemed lost on Scott.''
Scott, who has children, Mason, four, and Penelope, 23 months, with pregnant Kourtney, reportedly arrived at 10ak in his Bentley with a huge entourage in tow shortly after midnight and wasted no time letting his hair down.
Party-goers claim he was ''pretty wasted'' and didn't seem to mind being away from his girlfriend.
Meanwhile, North and her parents, Kanye West and Kim, were joined by a number of famous pals, including Ciara and her one-month-old son, Future, and fashion designer Rachel Roy, at a Coachella-inspired 'Kidchella' party at Kourtney and Scott's $8.45 million mansion, which they purchased earlier this year.
The couple spared no expense for the celebration, which took place almost one week after North's actual birthday last Sunday (15.06.14).
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