By many accounts, Sabrina Zunich had a difficult childhood.
The girl's parents, who struggled with substances and legal troubles while raising her outside Cleveland, abandoned her at the age of three, she went to live with her grandmother. But before long, Sabrina was placed in the juvenile system after she was caught stealing; the theft was to get money for drugs and alcohol.
The struggling teen seemed to have found a stable home when she was placed in foster care with Lisa and Kevin Knoefel in 2011. Friends of the couple described them as a perfect pair.
“I wanted a new beginning and to put all the past behind me, I wanted that picket white fence, the dinner on the table with siblings, you know something I never had. I wanted that structure with family,” Zunich said in an episode of “Dateline: Secrets Uncovered,” airing Thursday on Oxygen at 8/7 CT.
“My relationship with Lisa, it was at first good,” Zunich told producers from prison. “We would all spend time together. We’d go swimming in the backyard. I felt a part of the family.”
But less than two years later, Zunich would sneak into Lisa’s darkened bedroom and viciously stab her 178 times as Lisa Knoefel’s daughter, Megan, watched the brutal murder play out while screaming for help to save her dying mom. But authorities arrived too late.
“I could barely even see flesh color, here was so much blood on her,” Willoughby Hills Police Officer Randy Mullenax told "Dateline" reporter Josh Mankiewicz of the moment he found Lisa Knoefel dead on the floor of the family home's master bedroom.
Zunich was still at the scene, covered in blood. She was clutching a large serrated kitchen knife.
“It looked like she literally showered in blood,” Mullenax said.
Zunich was ordered to the floor then taken into custody. But it would be six months before investigators learned what had prompted the grisly killing.
Just two weeks before the murder, Zunich said, her foster mother told her that she’d need to leave their house.
“She was like, ‘I am sorry, but I don’t want you here anymore,’” she said. “My life was shattering before me — the betrayal, the abandonment — all that came to surface.”
Zunich also revealed another dark secret that she says prompted the killing: she had been having a sexual affair with her foster father, Kevin Knoefel, for around six to eight months before the November 2012 slaying.
Zunich claimed the murder had been his idea.
“When you are in love, you’d do anything for that person,” she later said from behind bars.
According to Zunich, the idea began small, with Kevin Knoefel sending her occasional text messages saying he hated his wife and believed she “just needs to go.” Over time, she said he promised her that with his wife out of the way, they’d buy a house of their own and that she could go to college and even play “mother figure” to the children.
The pair began to plot the best way to kill Lisa Knoefel, ultimately deciding that Zunich would stab her death, steal some valuables and stage the scene to look like a robbery and murder.
“Kevin picked out this bread knife and it was about a foot long and it had a rigid blade. He [said] to use this one because it would do more damage on the inside,” Zunich said.
Zunich said that on the night of the murder, she snuck into the bedroom and just stared at Lisa Knoefel for 10 to 15 minutes before she initially stabbed her with the knife.
“I hated Lisa, but it was only because she was triggering a lot of past issues,” she said. “It’s not all my fault, now I take responsibility because I did what I did, and I know it was wrong. But if it weren’t for him, it wouldn’t have happened.”
Kevin Knoefel, a truck driver, had been away for work at the time of the murder — but authorities say his behavior after his wife's killing drew suspicion. He began to cash in on Lisa’s $800,000 insurance policies hours after she was pronounced dead, then went on a lavish spending spree, buying cars, a camper and updating his house.
While there was no physical evidence of a relationship between Zunich and Kevin Knoefel, investigators believed Zunich’s story and he was arrested.
Zunich agreed to plead guilty to aggravated murder and testify against the man she said she once loved.
In his trial, prosecutors brought witnesses to the stand who testified they had observed inappropriate behavior between the teen and her foster father. Zunich herself took the stand to describe their illicit relationship.
Jurors ultimately convicted Kevin Knoefel of two counts of conspiracy to commit aggravated murder, three counts of complicity to aggravated murder and six counts of sexual battery for his sexual relationship with the teen, according to Cleveland.com. He was sentenced to life in prison with the possibility of parole after 30 years.
Zunich was handed the same sentence.
To learn more about the case, tune in to “Dateline: Secrets Uncovered” on Oxygen on Thursday at 8/7 CT.
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