Robert De Niro is still mourning the death of his grandson, Leandro De Niro Rodriguez.

The actor shared as much in an interview with People published Wednesday and said he was in “disbelief” when he heard the “awful” news.

Rodriguez died from an accidental overdose in New York City last summer at the age of 19. He was the son of Drena De Niro, Robert De Niro’s adopted daughter.

“It’s just a shock,” Robert De Niro said. “[I] never thought it would happen.”

“And I just then started thinking about all the things I could have, should have done maybe with him,” he continued. “I don’t know if that would’ve made a difference. And so that’s always playing through my mind. It shouldn’t have happened.”

Drena De Niro announced the news of Rodriguez’s passing in an emotional Instagram post on July 2, writing, “I don’t know how to live without you.” She had starred in multiple films with Rodriguez, including “A Star Is Born” (2018), before he was found dead.

Shortly after, she revealed the cause of his death when someone left an Instagram comment asking about the matter.

“Someone sold him fentanyl laced pills that they knew were laced yet still sold them to him so for all these people still fucking around selling and buying this shit, my son is gone forever,” Drena De Niro said.

Later that month, the suspected dealer, Sofia Marks, was arrested and federally charged with drug distribution.

Marks was reportedly arrested during an undercover sting by the New York Police Department, the Drug Enforcement Administration and the U.S. Department of Homeland Security on July 13. According to a criminal complaint, she had 156 fake oxycodone pills and $1,500 on her at the time.

“At least one of Marks’s counterfeit pills was purchased and taken by a teenager who subsequently died of a suspected overdose,” U.S. Attorney Damian Williams said in an accompanying statement. “The arrest was critical because, as we allege, Marks knew the pills could kill, and she continued selling them anyway.”

In August, New York City’s chief medical examiner confirmed that Rodriguez died from the “toxic effects of fentanyl, bromazolam, alprazolam, 7-aminoclonazepam, ketamine, and cocaine,” according to TMZ.

Rodriguez’s death came mere months after “Euphoria” star Angus Cloud died of an accidental overdose at 25. Dana Carvey’s son, Dex Carvey, also died from a fentanyl-related overdose at 32 in November.

According to the Centers for Disease Control, the number of drug overdose deaths in 2021 was more than six times higher than in 1999 — with more than 75% of the 107,000 overdose deaths in 2021 involving an opioid.

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