Erin Moran's final autopsy report confirms her cause of death.
The report (including toxicology results) obtained by ET confirmed that the Happy Days star died naturally from complications of stage 4 cancer. No illegal narcotics were involved in her death.
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Moran, 59, was found unresponsive on April 22 by authorities in Indiana after they got a 911 call. Earlier reports from the Harrison County Sheriff's Department and the Harrison County Coroner's Office stated that the actress "likely succumbed to complications of stage 4 cancer."
The actress was best known for her role as Joanie Cunningham on Happy Days. The show ran for 11 seasons, with Moran portraying the character from 1974 to 1984 and reprising the role in the short-lived 1982 series Joanie Loves Chachi alongside Scott Baio.
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Before Moran's cause of death was announced, Baio made headlines when he insinuated that the actress died as a result of past substance abuse issues.
"For me, you do drugs or drink, you're gonna die," Baio said during an appearance on The Bernie & Sid Show. "I'm sorry if that's cold, but God gave you a brain, gave you the will to live and thrive and you gotta take care of yourself."
He quickly took to Facebook to clarify his comments and explained how he was only asked about her troubled past. "I was asked ONLY about Erin's troubled past due to drug & alcohol abuse. I was still upset and said I felt that living that kind of a lifestyle will catch up with you and nothing good would come of it," Baio wrote. "THIS WAS BEFORE THE CAUSE OF DEATH WAS ANNOUNCED STATING STAGE 4 CANCER."
"I'm also trying to process this loss," he added. "Please stop assuming the worse in me. I'm a compassionate person. I'm very heartbroken over her passing, especially since it was cancer."
RELATED: Scott Baio Slams Controversy Over His Remarks About Erin Moran's Death: 'Stop Assuming the Worse In Me'
Moran's husband, Steven Fleischmann, also penned an open letter about his wife's last days and her cancer. "It got so bad, so fast," he wrote. "I fell asleep, woke up about a hour later, still holding her hand and she was gone. She was just gone."
Watch the video below for more on Moran's death.