Boy Executes Woman Who Raised Him Then Blames Alternate Personality Based on 'Jeff the Killer'

No one disputes how Heidi Taylor died — after more than five dozen stab wounds and with a final, fatal shot to the head — but more than a year later, the teenage boy convicted of murdering her in their home maintains he is not to blame.

"I am so scared. I didn't want to kill her," Donovan Nicholas, then 14, told an emergency dispatcher in a shaky voice last April from his kitchen in Urbana, Ohio. There he lay bleeding from an inadvertent leg wound sustained while he was stabbing the 40-year-old Taylor with a kitchen knife, over and over.

Voice stuttering, Donovan explained to 911 that someone he called Jeff, modeled after the fictional horror character "Jeff the Killer," lived "inside" him. It was Jeff, he said, who was in control while killing Taylor, the longtime girlfriend of Donovan's father and the woman who raised him.

Later investigators would learn that Donovan had dressed like Jeff during the murder, even slashing his mouth with a small blade in an impression of Jeff's rictus. ("Jeff the Killer," an Internet-born horror character, traces back to around 2008 and is usually depicted as white-skinned homicidal maniac without eyelids or a nose.)

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In black pants and a black shirt, according to prosecutors, Donovan hid near the front staircase of his home on the afternoon of April 6, 2017, and then called Taylor down to die. A chaotic and bloody scramble ensued as Taylor pleaded for Donovan to stop attacking her, to call 911.

At one point he got a drink of water and, when Taylor headed for her bedroom upstairs to get her phone, he raced ahead of her, at last retrieving his father's 9-mm handgun from the nightstand.

Twice he had to load it, but he only had to shoot her once.

"I hate Jeff so much. … He couldn't have taken somebody else, no," Donovan told 911 after Taylor was dead. "He took me to be his person."

"I don't want to die in prison," Donovan said. "I swear it wasn't my fault."

Jurors disagreed: In June, days after his 16th birthday, he was convicted as an adult of aggravated murder and sentenced to life in prison. He will be eligible for parole after 28 years.

Champaign County Prosecutor Kevin Talebi says that Donovan, grown resentful and sunk deep into homicidal fantasy, was pushed over the edge after Taylor decided to take his phone away when she discovered he was sexting with an out-of-state girlfriend.

Talebi vigorously disputes Donovan's claims of an alternate personality, dismissing it as the excuse of a vicious mind. He notes the psychologists who examined Donovan found him to be legally sane and did not agree that he had dissociative identity disorder as Donovan's attorney, Darrell Heckman, believes.

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But, with Donovan appealing, the case is likely to carry into next year. Heckman argues he is severely mentally ill and in critical need of treatment in the juvenile system, where he should have remained.

"There is an important societal issue as to what age do we give up on children for their rehabilitation prospects and what age do we not?" Heckman tells PEOPLE.

As Talebi does, Heckman also cites the evaluations done of Donovan, but for the opposite reason: Two of the psychologists found that Donovan, who previously struggled with depression and self-harm, had notable mental health issues even if the exact diagnosis was less clear.

"It's got feathers, it flies. You don't really have to identify the bird to know that it's a bird," Heckman says.

Taylor's children, who were raised in a blended family with Donovan and his father, Shane Nicholas (who declined to speak with PEOPLE), aren't sure what to believe.

In the aftermath of the murder, stunned and mourning, they have gathered around Taylor's memory, which they don't want lost amid the case's grim details.

Daughter Alyssa Nicholas described Taylor as her "best friend" and a doting grandmother to her young girls — "the type of grandma who kept cookie dough in the freezer so that she had cookies on demand," she recalled in court.

"For my sanity, I would like to think there is something truly wrong [with Donovan] for him to do something so horrific," Alyssa, 23, tells PEOPLE.

Taylor's son, 21-year-old Todd Taylor, is more skeptical about what is going on inside Donovan's head, but still he wrestles with the savage reality of what Donovan did last year.

At his sentencing in July, Donovan offered his regret and said he would like to receive treatment. In conversations with his family from behind bars, Donovan sounded much the same.

Todd recalls one meeting where he apologized, over and over.

"How do you know it's sincere though?" Todd wonders. "Anybody can say sorry."