By Kathleen Brady Shea, Managing Editor, The Times

Toni Lee Sharpless, 33, of West Brandywine Township, was last seen in Philadelphia on Aug. 23, 2009.

The sudden disappearance of a Chester County nurse and mother four years ago continues to be shrouded in mystery.

Toni Lee Sharpless, 33, of West Brandywine Township, was last seen about 4 a.m. on Aug. 23, 2009. She was driving her black 2002 four-door Pontiac Grand Prix after having left a small gathering at the Penn Valley home of former 76er Willie Green. She then vanished, leaving an unsettling dearth of clues.

Since then, her anguished parents, Donna and Peter Knebel, have pursued every possible avenue to secure their daughter’s safe return: conducting searches and interviews, appearing on national TV, distributing flyers, even giving their blessing to a Texas firm that used sonar equipment to plumb the Schuylkill River.

The parents of Toni Lee Sharpless, who disappeared four years ago, hope that circulating her photos may prompt someone with information to come forward.

Although Sharpless’ car was picked up at least once by a license-plate reader, it was never recovered. Neither was her phone, which was never used, nor her credit cards.

“In this day and age of surveillance and technology – and so much information with Facebook and social media – I just don’t know why someone hasn’t found something,” said Peter Knebel in a recent interview. “I feel as if we’re back to square one. We don’t know anymore now than we did four years ago.”

His wife agreed. “I’m almost right where I was four years ago,” said Donna Knebel. “There’s a painful, empty void. Lots of tips have come in, but nothing that’s solid.”

West Brandywine Township Police Chief Walt Werner said a couple leads came into the department as recently as a month ago; both turned out to be hoaxes. “I dread this time of year,” he said. “I still have no answers.”

Werner said his officers follow up on information they receive, but the majority  of the calls go to Eileen Auch Law, a Chester County private investigator who has assisted the family from the beginning. “She’s done a good job of keeping the case alive,” Werner said.

Donna Knebel said she appreciated Werner’s help and would be forever indebted to Law, who has attempted to verify alleged, far-flung sightings of Sharpless in places from Reading to Camden, N.J. “If it weren’t for her, I don’t know what I’d do,” said Knebel. “I rely on her so much; she tracks everything down.”

Law said she won’t stop. “I will never give up until Toni’s found,” said Law. She said she is motivated by Sharpless’ daughter, who’s is in the care of her grandparents, and the steadfast belief that the family deserves closure.

According to police reports, the evening before Sharpless disappeared, she decided to go out with a longtime friend, Crystal Johns. Her parents said they welcomed the news because their daughter, a single mother, had been working so hard that she had little time for any social life.

Johns told police that the pair was invited to Green’s Main Line house after meeting him at a Philadelphia nightclub. She said Sharpless apparently had too much to drink, and they were asked to leave. Once outside, Johns suggested that Sharpless, who had become uncharacteristically belligerent, should not drive. The two argued and Sharpless drove off alone, stranding Johns.

Johns later called Sharpless’ behavior highly unusual. Sharpless’ family said it likely resulted from a mix of alcohol, sleep deprivation, and medication for bi-polar disorder, an illness she had finally brought under control after struggling to get a diagnosis.

Police said Sharpless’ cellphone has not been used since she sent a text message to her daughter a few hours before leaving the party, urging her to get a good night’s sleep. Her credit cards have also not been used. Her car, with Pennsylvania tag DND-7772, was spotted by a machine that records license-plate numbers on Sept. 8, 2009, in Camden. Law said a Camden police officer told her a second hit occurred from a plate-reader within the city limits, but he declined to elaborate.

Law, who set up a Sharpless Facebook page and a website – www.MissingToniSharpless.com – to generate leads, believes Sharpless’ impaired condition could have made her vulnerable to being victimized.

Many of the tips have turned out to be pranks, she said. But some have given her pause. Earlier this year, Law received an anonymous letter that claimed Sharpless was killed after a fight with a Camden police officer. The letter writer said, “What happened to (Toni), I don’t really know. All I know is she had a run-in with the police and I was paid much-needed cash to get the car to a shop in Boston.”

The writer claimed to have received $5,000 to dispose of the car. Law said the writer referenced the correct vehicle identification number (VIN) for the Grand Prix. “I believe there’s a reason why they sent me this letter,” Law said. “I’m absolutely convinced there are people who know what happened.”

Donna Knebel said she was buoyed recently by news of the  discovery of the three girls in Ohio. “You just never know,”  she said. Several months ago, a woman approached Knebel in a grocery store and exclaimed: “You’re Toni Sharpless’ mom.” Knebel said she was dumbfounded, but the woman explained that she has two daughters and had been following the case closely.

In fact, the woman, who lives in Denver, Pa., told Knebel that she had talked to Law after seeing a woman in a cowboy hat that she believed was Sharpless. “She was very sweet and apologized for not taking a picture,” Knebel said.

Knebel said she gets momentary comfort from being proactive, whether she’s preparing a new poster for distribution or taking time for an interview. If someone thinks they see her daughter, grab a phone and take a photo, she urged. And she hopes people will circulate photos of her daughter so that the “person who knows something” will see them. “Not knowing is so hard,” she said.

Werner said he’s convinced that the truth will surface at some point. “I always think there’s hope,” Werner said, insisting that someone knows what happened. “If anyone has information, please help us find Toni and bring her back to her parents and daughter,” he said.

Peter Knebel agreed that “someone must know” what occurred the night of Aug. 23, 2009. “She didn’t just vanish into the night,” he sald. “I just can’t believe after four years that no one has come forward. Every night we pray that we get some news on Toni,” he said.

Anyone with information should call West Brandywine Township police at 610-380-8201 or Law at 610-388-1776.