DOYLESTOWN, Pa. (CBS/AP) – A woman plead guilty and was sentenced to life in prison Friday for her role in the 2016 rape, murder and dismemberment of her 14-year-old daughter, Grace Packer. Sara Packer agreed to plead guilty in exchange for a life sentence.

Packer admitted in court last week that she plotted to kill her adoptive daughter, Grace Packer, saying she hated the teenager and “wanted her to go away.”

(credit: CBS3)

Sara Packer’s boyfriend, Jacob Sullivan, pleaded guilty to first-degree murder and related offenses and was sentenced to death.

(credit: CBS3)

Packer says she helped Sullivan tie Grace up and watched as he raped and strangled her. The couple stored Grace’s body in cat litter for several months before dismembering it and dumping it in a wooded area.

(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)