He, like Jackett, gave a DNA sample to investigators and later said the results cleared him.

More than a year after the murder, on Jan. 9, 2003, Cape and Islands District Attorney Michael O'Keefe held a news conference to ask the public's help in finding the mystery man who slept with Worthington just before her death.

The prosecutor said the man was "not necessarily" her killer, but certainly had vital information to the investigation. Worthington kept a detailed diary, according to Jackett, but apparently did not disclose a new lover.

For friends, used to hearing every detail of Worthington's life, the mystery lover is puzzling.

"It now seems to me that she told everyone everything -- from her closest friends to a woman who babysat for her once or twice.," Radlauer said. "If this is someone she had met once or twice though, she wouldn't necessarily have called everyone the next morning."

But how would Worthington have met someone? A few months before they announced their search for Worthington's last lover, Massachusetts investigators traveled to New York to interview friends, including Radlauer. The officers wanted to know if Worthington drank a lot and asked about rumors that she was frequenting bars on the Cape nightly before her death.

"They said they were unhappy with the information they were getting on the Cape," Radlauer said. He added that bar-hopping just didn't sound like Worthington, a mother so attentive that she put Ava in a car seat for a 9-block cab ride, "I just don't see it. She didn't drink a lot." Worthington's relatives are no longer talking publicly about her death. One of her cousins, Jan, a screenwriter, is writing a television movie about the murder.

Neither the $25,000 reward nor the announcement about the mystery man yielded the substantial tips investigators had hoped. Only about 20 people, including the usual crackpots and psychics, phoned in.

"We are continuing to look for that individual and we are continuing to send (evidence)for (lab) testing," said O'Keefe, who has refused to characterize the range of evidence recovered from the crime scene.

He added that a year without an arrest may seem long for the family, but "is not all that unusual."

Ava Worthington, now approaching her fourth birthday, lives outside Boston with her mother's high school friend, Amyra Chase, and her husband. Once a week, she visits Jackett. Last month, Chase said Ava was doing "very well."

"She has enlightened our family," said Chase.