Prosecutors said Jennifer Daugherty was targeted by Angela Marinucci, who viewed the victim as a rival for the romantic affection of a man.
VIDEO: Teen Found Guilty In Greensburg Torture, Slaying VIDEO: Victim's Sister Talks After Verdict
Later this year, that man, Ricky Smyrnes, faces the possible death penalty at trial for his alleged role.
Daughtery's family members brought her ashes to the sentencing and told Channel 11's Courtney Brennan, "This is Jennifer. What they did is so awful we couldn't have an open casket or burial. We brought her here today for justice."
"We decided to bring Jennifer today because she deserved to be here. She should be here," said Daugherty's sister, Joy Burkeholder. "This is the best we could do."
After the sentencing, Marinucci spoke to Channel 11 News and said that she wanted to thank her supporters, including a woman in prison with her.
Brennan asked Marinucci if she was sorry and she responded with a simple "yes."
Marinucci told the judge that she hoped Daugherty's family would eventually forgive her. Daugherty's family cried in the courtroom as her mother and sister gave their victim impact statements.
"We finally have one of the demons where they belong and this is for all children who are mentally challenged and autistic," said Daugherty's aunt Cynthia Strauss.
A Westmoreland County jury deliberated for less than four hours before convicting Marinucci earlier this year in the February 2010 death of Daugherty, 30, after eight days of testimony.
District Attorney John Peck said Marinucci instigated the 36-hour ordeal in a dingy apartment that was shared by five other defendants awaiting separate trials.
Peck charges they beat Daugherty with a vacuum hose, a crutch and a towel rack -- as well as their fists -- and forced her to undress while pouring water, oatmeal and spices on her -- including onion powder thrown in her eyes. She was then forced to drink a cocktail of human waste, laundry bleach and prescription drugs, which the defendants reportedly thought would kill her.
When it didn't, Peck said she was stabbed by defendant Melvin Knight, 21, apparently on orders from Smyrnes, 25, the alleged focus of the deadly romantic rivalry.
Peck is pursuing the death penalty against both as well as Knight's girlfriend, Amber Meidinger, 21, who testified against Marinucci and acknowledged mixing and forcing Daugherty to drink the concoction.
Peck said the case was difficult because Marinucci didn't personally kill Daugherty, but was charged as an accomplice and co-conspirator. The case rested largely on statements Marinucci made to several county prison inmates since her arrest shortly after the murder last year -- as well as some early statements to police and Meidinger's testimony.
In Marinucci's case, DeMatt argued it was unlikely the five adult defendants would do the bidding of Marinucci, who was a 17-year-old high school senior at the time. The other two defendants are Peggy Miller, 28, and Robert Masters, 38, another couple who lived at the apartment and are charged largely because they allegedly helped keep Daugherty there, though they're also accused of participating in some of the abuse.
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