Christopher "Big Black" Boykin will be missed.
The Rob & Big star died on Tuesday morning, ET confirmed, and on Wednesday, his ex-wife, Shannon, took to his Twitter account to write a sad message for his fans. Shannon and Boykin had a daughter together, 9-year-old Isis.
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"This is Shannon, Big Black's ex-wife, I'm heartbroken to tell you of Black's passing," Shannon wrote on his official Twitter page. "He's everything to me and Isis and we will miss him."
Boykin, a former U.S Navy serviceman, was 45 years old. While his cause of death is still unknown, TMZ reported that "multiple people connected to Chris... believe it was a heart attack."
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Skateboarder Rob Dyrdek, who starred with Boykin in their beloved MTV reality show from 2006 to 2008, also took to social media to share his grief.
"My heart is broken I don't want to write this post," Dyrdek, 42, Instagrammed alongside a photo of the two together. "I don't want to believe that this is reality. I am so thankful for you. We truly were brothers that lived an unexpected unforgettable adventure. I just can't fathom that it would end so suddenly. You will forever be in my heart."