Robert De Niro says grandson’s fentanyl overdose ‘shouldn’t have happened’

Robert De Niro will forever mourn the death of his late grandson Leandro De Niro Rodriguez who died of an overdose in July. He was 19.

"It’s just a shock," he told People magazine. "[I] never thought it would happen."

One month after Leandro died, New York's Office of the Chief Medical Examiner confirmed to Fox News Digital that his cause of death was due to the "toxic effects of fentanyl, bromazolam, alprazolam, 7-aminoclonazepam, ketamine, and cocaine." 

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De Niro remembered feeling "disbelief" upon hearing about Leandro's death. Leandro is the son of De Niro's oldest daughter, Drena, with ex Diahnne Abbott. 

The "Killers of the Flower Moon" actor adopted Drena when he and Diahnne married in 1976. They divorced 12 years later in 1988. 

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"My grandson, on July 2nd of last year, he was … he overdosed with fentanyl," De Niro said. "He was just about … going to be 20. It's awful."

"And I just then started thinking about all the things I could have, should have done maybe with him. I don't know if that would've made a difference. And so that's always playing through my mind."

Rodriguez's manner of death was ruled an accident, according to the medical examiner.

De Niro added, "It's not a good thing for anybody. It shouldn't have happened."

Drena, an actress and filmmaker, worked alongside her son in multiple projects, including "A Star is Born."

Sofia Haley Marks, 20, was arrested in connection with Rodriguez's death in July. Marks allegedly sold Rodriguez drugs before he was found dead July 2 in his Manhattan apartment. 

She appeared in a Manhattan federal court two weeks later on three federal narcotics charges and agreed to remain behind bars until she requests bail at a later date. Prosecutors said at the time that they would oppose a request for her release.

"I’m deeply distressed by the passing of my beloved grandson Leo. We’re greatly appreciative of the condolences from everyone. We ask that we please be given privacy to grieve our loss of Leo," the Academy award-winning actor said in a statement shared with Fox News Digital.