Prosecutors said it was part of an alleged "rape-murder fantasy" acted out by Jacob Sullivan and the victim's adoptive mother Sara Packer
Over two years after a Pennsylvania teenager’s dismembered body was found by hunters in October 2016, her mother’s boyfriend has pleaded guilty.
Jacob Sullivan of Horsham, 46, pleaded guilty on Tuesday in the rape, murder and dismemberment of 14-year-old Grace Packer, according to the Associated Press, KYW News and the Bucks County Courier Times.
Grace was beaten and raped before her remains were preserved in cat litter for three months. Then, Sullivan chopped up her body and dumped it in a remote area of Pennsylvania.
Prosecutors said it was part of an alleged “rape-murder fantasy” acted out by Sullivan and Grace’s adoptive mother Sara Packer, who was dating him at the time and formerly worked as a foster parent and child welfare worker.
Packer, 43, who is scheduled to testify against Sullivan, is expected to plead guilty and be sentenced to life, according to her attorney, Keith Williams.
Williams did not immediately respond to PEOPLE’s request for comment.
A jury will be selected next month for Sullivan’s death penalty proceeding.
• Want to keep up with the latest crime coverage? Click here to get breaking crime news, ongoing trial coverage and details of intriguing unsolved cases in the True Crime Newsletter.
The attack on Grace began on July 8, 2016. Sullivan told investigators he and Packer drove the girl to a home in Richland Township, where he punched her several times in the face and split her lip open.
Sullivan and Packer proceeded to give Grace an overdose of pills, then bound and gagged her and left her to die in the hot attic. Much to their shock, Grace was still alive.
The pair strangled and suffocated her until she died before they packed Grace’s body in cat litter to mask the odor and left it in the attic for three months.
Packer previously filed a missing persons report with Abington Township Police, three days after her adopted daughter’s killing, telling authorities the girl probably ran away.
“Unfortunately, Grace Packer was a disposable child to these people,” Bucks County District Attorney Matthew Weintraub previously said in a statement obtained by PEOPLE. “Who will now speak for Grace Packer? We will.”
Sullivan’s plea hearing will continue on Wednesday.
If you suspect child abuse, call the Childhelp National Child Abuse Hotline at 1-800-4-A-Child or 1-800-422-4453, or go to http://www.childhelp.org. All calls are toll-free and confidential. The hotline is available 24/7 in more than 170 languages.