Rapper Grand Daddy I.U., Known for His Debut Album Smooth Assassin , Dead at 54

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Rapper Grand Daddy I.U., who was once signed under the record label Cold Chillin' Records and best known for his debut album Smooth Assassin, has died. He was 54.

His representative, Raya, CEO of FNBG Records confirmed the news to PEOPLE on Tuesday. She also posted a statement on her Instagram account, writing, "No, I am not okay. I'm devastated."

"Anyone who really knows me knows how much pure love and respect I had for him and out of respect for him and his family, I'm staying quiet right now," the statement read. "I do not need to post pictures nor stories to profess anything. I pray for a peaceful and easy transition."

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The late rapper's longtime friend, hip-hop producer Pete Rock, also posted a tribute on his Instagram, writing in the caption, "Grand Daddy I.U. died peacefully in his sleep 😢😔."

Grand Daddy I.U.'s cause of death has not yet been revealed. "The family is awaiting results from his autopsy," his representative told PEOPLE.

Born on Aug. 23, 1968, in Queens, New York, the rapper — real name Ayub Bey — pursued a career in music after being encouraged by his brother Kay Cee.

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He was signed to the record label Cold Chillin' Records in 1989 by Biz Markie after giving Markie a demo tape. The following year, Grand Daddy I.U. released his debut studio album, Smooth Assassin, which included his songs "Something New" and "Sugar Free."

Grand Daddy I.U. went on to appear as a guest on several hip-hop albums in the 1990s including Big L's Lifestylez ov da Poor & Dangerous and Positive K's The Skills Dat Pay Da Bills.

After parting ways with Markie, he released his sophomore album, Lead Pipe, in 1994. Grand Daddy I.U. released his third album, Stick to the Script, in 2007. His latest single "Stay Fly" dropped in July 2021.

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Following the news of his death, LL Cool J honored the late rapper by posting his photo on Instagram.

"Rest in power King. HipHop was in your DNA. @granddaddy_iu Thank You for your contribution.🙏🏾🕊," he wrote in the caption.