Lionel Dahmer, the father of infamous serial killer Jeffrey Dahmer, has died at the age of 87.
According to The New York Post, Lionel passed away from unknown causes while under care in Medina County, Ohio. The exact date of his death is unknown.
The chemical analyst lived out the final years of his life in relative isolation, preferring to remain away from the spotlight in his hometown of Seville, Ohio.
His death was confirmed by an employee at the Medina County Health Department, The U.S. Sun reported.
In 1978, Lionel divorced Jeffrey's late mother, Joyce, and married his stepmother Shari Dahmer - who passed away this year aged 81. She is believed to have died from complications related to health problems she experienced in recent years.
The couple was thrown into the spotlight in 1991 after their son was revealed as the serial killer who tortured, murdered, and cannibalized men he lured to his Milwaukee apartment.
Even after the terrifying truth about their son's cannibalistic crimes came to light - which were his murders of at least 17 men and boys between 1978 and 1991 - they stood by his side.
The pair even continued to visit him after he was incarcerated in 1992.
Jeffrey was subsequently murdered in prison in 1994, at the age of 34, by fellow prisoner Christopher Scarver. His life and twisted crimes were once again brought to mainstream attention last year in Netflix's hit documentary, Monster: The Jeffrey Dahmer Story.
Despite living a private life, Lionel couldn't escape his son's name due to the ten-part series, and his caretaker complained that fans would show up at his door, acting "hostile and aggressive," per The Sun.
Back in 1994, the father-of-two penned a book titled A Father’s Story which told how he had brought up his son from his perspective and tried to examine what made him commit the crimes he did.
He admitted to being aware of the serial killer's heavy drinking, aimless nature, and infatuation with dead animals.
During an interview on Good Morning America in the 1990s, Lionel said revealed he felt could be the reason for his son's actions: "The closest I could come to why - to give some type of causality for all this - is that I think it was a cumulative thing.
"I think there were several events in his life starting with the hernia operation, his concern about having his penis being cut off which he expressed to his mother at the time, I didn't even know about that until the trial in February '92.
"That plus a blow to the back of the head, plus I don't know these various incidents, going around and getting roadkill. All these things came to a cumulative ending and it hooked on, I firmly believe it hooked into his sexuality at age 14 or 15," he explained.
"There really were no overt signs," he stated about his son's early behavior, adding: "He wasn't foaming at the mouth or talking to himself in his sleep, or acting in a weird fashion."
Furthermore, he said that Jeffrey was a "very wonderful little boy" but that he was "very shy" and "very reclusive" during his youth. He also urged parents to keep track of their children's behavior even if they don't show alarming signs.
"That's another thing that I would like to come across to parents, even if their child seems innocuously shy try to draw out their concerns and anger," he shared. "Because if they don't talk to anyone there's no reality checking at all, and what they can't distinguish between fantasy and reality."