Pennsylvania Man and Girlfriend Allegedly Acted Out ‘Rape-Murder Fantasy’ on Her 14-Year-Old Daughter

Pennsylvania authorities say a 14-year-old girl whose dismembered body was found by hunters in October was allegedly strangled to death in July by her adoptive mother’s boyfriend who beat her and sexually assaulted her over an 18-hour period, PEOPLE confirms.

It was part of an alleged “rape-murder fantasy” acted out by the suspects, Bucks County District Attorney Matthew Weintraub said in a statement obtained by PEOPLE.

Sara Packer, 41, and her 44-year-old boyfriend, Jacob Sullivan, face multiple charges. Prosecutors allege Sullivan preserved Grace Packer’s remains in cat litter for three months before chopping up her body and dumping it in a remote area of Pennsylvania.

Grace was reported missing by her mother in July. Her corpse was found on Halloween in a mountainous region of the state, just south of Scranton.

Weintraub’s statement alleges that Sullivan and Packer began plotting the teen’s murder in late 2015, soon after Grace returned from a stay with extended family members in North Carolina.

“Unfortunately, Grace Packer was a disposable child to these people,” reads Weintraub’s statement. “Who will now speak for Grace Packer? We will.”

Weintraub said he may seek the death penalty against Sullivan and Packer, who took Grace in as a foster child at the age 3 and later adopted her.

According to Weintraub, Sullivan and Packer allegedly forged a suicide pact and, on Dec. 30, unsuccessfully attempted suicide by prescription pills. Sullivan has been in the hospital ever since.

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Sullivan was arrested Saturday after allegedly telling several staffers at Abington Hospital-Jefferson Health in Abington that he was responsible for the teen’s slaying.

“Under subsequent questioning by Bucks County detectives, he revealed in detail how the girl was assaulted and killed over the course of about 18 hours,” Weintraub’s statement reads.

Weintraub says the attack on Grace began on July 8, 2016. Sullivan allegedly told investigators he and Packer drove the girl to a new home in Richland Township, where he allegedly punched her several times in the face, splitting her lip open.

“The two adults then took the teen to the third floor of the residence, where Sara Packer watched as Sullivan raped her daughter,” Weintraub’s statement alleges. “Sara Packer then left to buy Tylenol PM and other drugs for sedating Grace. Telling her the drugs would help minimize her pain from the assaults, the adults gave her an overdose of pills, then bound and gagged her and left her to die in the hot attic.”

Weintraub alleges that Packer and Sullivan said they left the house for the rest of the day, returning the next morning. Much to their shock, Grace was still alive, Sullivan allegedly told investigators.

“He strangled and suffocated her until she died,” claims Weintraub’s statement. “Packer and Sullivan then packed Grace’s body in cat litter to mask the odor and left it in the attic for three months.”

Weintraub called the crime “a rape-murder fantasy that was shared by Jacob Sullivan and Sara Packer, and they acted it out.”

Sullivan has been charged with homicide, rape, involuntary deviate sexual intercourse, unlawful restraint, kidnapping, possessing instruments of crime, endangering the welfare of a child, abuse of corpse, simple assault, tampering with physical evidence, and corresponding conspiracy charges.

Packer was arrested on homicide, kidnapping, unlawful restraint, possessing instruments of crime, endangering the welfare of a child, abuse of corpse, simple assault, tampering with physical evidence, and conspiracy to commit rape charges.

Both Sullivan and Packer are being held without bail and have yet to enter pleas to the charges against them.

Weintraub’s statement alleges Sullivan shouted “I’m sorry for what I did” to reporters as he was being led into a courthouse Saturday for his arraignment.

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Packer filed a missing persons report with Abington Township Police three days after her adopted daughter’s killing, telling authorities the girl probably ran away.