"He's going to go off the deep end. It's really bad. It's about to get dark," the source added.
Disick and Kardashian officially called their romantic relationship off in 2015 after nearly a decade of dating on and off. He featured regularly on Keeping Up With The Kardashians despite the split as a co-parent to the couple's children.
Yesterday news of Kardashian's engagement to Blink-182 band member Travis Barker was revealed on social media.
According to TMZ friends and family of the pair were there to witness Barker and Kardashian stroll down the beach to the extravagant display where Barker got down on one knee.
Taking to Instagram after the grand gesture, sister, Kim Kardashian gave us a look at the gorgeous ring Barker proposed with.
It was only earlier this month when the pair caused speculation after the singer shared a photo of a wedding dress and a tux. He uploaded the post without a caption, leaving many fans wondering if they had already tied the knot.
The two were confirmed to be dating in January this year after a source close to the pair told US Weekly "They have been close friends for years and have been dating for a couple of months. Travis is very smitten with Kourtney and has been for a while."
While the match might not have been predicted by many, the pair have long moved within the same social circles and lived in the same Calabasas gated community.
Kourtney has three children with her ex-partner Scott Disick, whom she separated from in 2015.
Barker has two children from a previous marriage.
Barker's ex Shanna Moakler has hinted at her displeasure over the news.
Moakler, a former pageant queen, posted an Instagram Story on Monday that simply showed the text: "Temporarily Closed for Spiritual Maintenance."
Since Barker and Kardashian started dating in November last year, Moakler has been open about her disdain for the pairing.
Moakler, who was married to Barker for four years, told People earlier this year that she was "very much over" her ex and labelled his very public relationship with Kardashian as "weird." She also accused Barker of having an affair with Kim Kardashian, Kourtney's younger sister, while they were still married.
Moakler and Barker were married in 2004, before divorcing in 2008. They have two children together, son Landon Asher Barker, 18, and daughter Alabama Luella Barker, 15.
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