Accused double murderer Nick Reiner got addicted to heroin at the age of 16 after leaving one of his first stints in rehab, a report details.

Many revelations have emerged about Reiner, 32, who is set to be charged for the brutal December 14 stabbing deaths of his parents, famed film director Rob Reiner and his wife, Michele Singer, including the revealation that he has been undergoing changes of schizophrenia medications that had him “out of his head.”

But the director’s son has had issues with substance abuse most of his life and it started when he was in his teens, the New York Post reported.

The screenwriter’s own comments have come back to light where he admitted to his early addictions.

Back in 2016, Reiner told the Dopey podcast that, “I went to a wilderness program in Utah. It was called Second Nature, and I met a kid there from LA and, at the time, he was kind of a hardcore Venice kid.”

(L-R) Rob Reiner and Nick Reiner attend “Being Charlie” AOL Studios In New York on May 4, 2016 in New York City. (Adela Loconte/WireImage)

“I met him when I was 16 and then, I was 18, I was in a sober living [facility], and I call him up because I knew he was really into heroin at the time,” he continued.

“The point of the story is that the seed of heroin got planted by the first time I was ever in rehab and the person I got it from was a guy that I met in rehab like three years down the line,” Reiner said, adding, “For all the negative that I think it did to me, it also exposed me to a larger demographic of people.”

The rehab organization Reiner was sent to was founded in 1998 takes kids ages 13 to 17 out to a wilderness area to help them try and overcome their addictions.

Nick Reiner has been in and out of rehab more than a dozen times and was most recently undergoing treatment in a luxurious mental health facility in Los Angeles that cost the Reiner family $70,000 a month.

It has also been theorized that Reiner could use his father’s money to help pay his legal bills despite a California law that maintains that a suspect who “intentionally killed” someone can’t receive money from the victim’s estate, the Post added in an earlier report.

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