Photo: Michael Tullberg/Getty

HOLLYWOOD, CALIFORNIA - JANUARY 30: (L - R) “Eight Is Enough” actors Jimmy Van Patten, Connie Needham, Dianne Kay, Laurie Walters and Adam Rich attend the Los Angeles premiere of the musical “Hello Dolly” at the Pantages Theatre on January 30, 2019 in Hollywood, California. (Photo by Michael Tullberg/Getty Images)

Adam Rich’s cause of death has been confirmed.

According toa reportfrom the Los Angeles Medical Examiner’s office, Rich died on Jan. 8 due to “effects of fentanyl.” The report listed the manner of his death as an accident.

Rich was just 54 years old when he was found dead inside his home earlier this year. His cause of death was initially deferred pending further investigation, but law enforcement sources claimed there was no sign of foul play when the actor’s body was discovered,TMZreported.

Rich was best known for appearing in the 1970s television showEight Is Enoughas Nicholas Bradford, the youngest child of Tom Bradford (Dick Van Patten) and his wife (Diana Hyland).

Because he was 18 at the time the movies began production, he joked to PEOPLE that he’d gotten “a lot less cute” since the original series.

Tony Korody/Sygma/Sygma via Getty Images

“Eight is Enough”, Dick Van Patten (top), (bottom, L-R) Grant Goodeve, Adam Rich and Willie Aames

Rich’sEight Is Enoughcostars mourned his death in the days following the news, and revealed they kept close friendships with the child star in adulthood.

Willie Aames, who played Rich’s brother on the family show, wrote anemotional Facebook postabout their friendship. “This morning [my wife] Winnie woke me with the heartbreaking news of Adam Rich’s passing,” he wrote. “I’m gutted. Adam was more than a colleague. He was very much my only little brother. A lifelong friend.”

In another part of the statement, Aames also revealed Rich was considering a return to acting before his death. “These last few years Adam had dreams of renewing his career. He was one of those kid actors that our generation will always remember.”

Costar Grant Goodeve opened up to PEOPLE about howspending time with Rich had “inspired” to pursue fatherhood.

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On-screen stepmother Betty Buckley also shared anInstagram tributereading, “Adam Rich was a light and my young pal for the four seasons I was blessed to work with him onEight Is Enough. I adored him and loved working with him in our scenes together on the show. He was so sweet, funny, fresh and natural. He brought a lot of joy to all of us on the show and to our audiences. Adam and I have remained friends all of these years. His love and support have always meant a lot to me.”

source: people.com