In 2000, Elizabeth Porter, who also goes by Beth, testified before a grand jury that she and Greineder met in 1998 while she worked for the Quincy-based Commonwealth Entertainment escort service and that they had sex at a hotel.

Porter was recently questioned by Massachusetts police detectives investigating the stabbing death of fashion writer Christa Worthington in her Truro, Mass. home, the Boston Globe and Boston Herald reported Tuesday. A source familiar with both the Greineder and Worthington cases confirmed that Porter is connected to both.

"She is one and the same," the source told Courttv.com.

Police refused to comment on the link between Porter and the Cape Cod victim's father, 72-year-old retired lawyer Christopher Worthington of Weymouth, Mass. The report is the latest twist in a bizarre murder case beginning to attract national media attention.

Porter, a Quincy, Mass. resident who is in her 20s, reportedly told some people that she was the stepsister of Christa Worthington. The 46-year-old freelance fashion writer who work appeared in Elle, Harper's Bazaar and other major publications was stabbed to death and apparently lay dead in her home for several days before her friend and former boyfriend, Tim Arnold, found her body Jan. 6, according to news reports.

Worthington's 2 1/2-year-old daughter, Ava Gloria Worthington, was in the home but was not harmed. Ava's father, a married father of six, is fighting to obtain custody of Ava despite a provision of Worthington's will that seeks to have another couple raise the child.

There is no telephone listing for Porter at the Quincy rooming house where, several newspapers reported, Christopher Worthington rented an apartment for her and another man. State police would not comment on their interest in Porter.

The Boston Globe story quoted several close friends of Christa Worthington as saying that she had been distraught over her father's relationship with Porter, who was much younger. Christa Worhtington's mother, Gloria Worthington, a landscape painter, died in 1999.

In the Greineder case the prosecution argued successfully that the 60-year-old defendant viciously attacked and killed his wife, Mabel Greineder, to end his marriage and continue his secret pursuit of prostitutes and sexual liaisons arranged over the Internet.

The investigation into Christa Worthington's killing continues.