A Pennsylvania mother has pleaded guilty to multiple charges related to her 3-year-old son’s torture and death — and has agreed to testify against her former boyfriend in his upcoming murder trial.
Jillian Tait, 33, pleaded guilty to conspiracy to commit murder and child endangerment in the 2014 death of her 3-year-old son, Scott “Scotty” McMillan.
Charging documents obtained by PEOPLE describe the boy’s violent death. “Scott McMillan had been punched and beaten with blunt and sharp objects, whipped, taped to a chair with electrical tape and beaten, hung up by his feet and beaten and suffered other acts of violence,” authorities said.
In a 2014 court appearance, District Attorney Thomas Hogan called Scotty’s death “an American horror story.” He alleged to the judge that regular spankings soon became “concentrated, repeating, escalating abuse.” In a three-day period November of 2014, Hogan alleged that the boy “was systematically tortured and beaten to death.”
In pleading guilty, Tait will avoid the death penalty and will serve as a “critical witness” in the case against Gary Lee Fellenbaum, a 25-year-old man who she once dated, Hogan said.
Fellenbaum has been charged with murder and faces the death penalty. According to prosecutors, Tait and met Fellenbaum while the two worked at Wal-Mart. They moved into a mobile home together, along with Fellenbaum’s wife and daughter and Tait’s two children, then aged 6 and 3.
Prosecutors allege that the couple bought pizza, went shopping and even had sex as Scotty lay dying from wounds he sustained from the alleged abuse.
In court on Monday, the prosecution said that Tait “accepts responsibility” for her part in her son’s death, but alleged that Fellenbaum actually killed the boy.
Fellenbaum has pleaded not guilty. His attorney did not return PEOPLE’s call for comment.
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Tait’s lawyer, Laurence Harmelin, told the court that Tait is ready to testify against Fellenbaum. “She is looking forward to putting the matter behind her,” Harmelin said, according to ABC News. “”She will have a lot more to say at sentencing.”
Tait faces a prison sentence of 64 to 128 years.