PLEASANTON — Shirley Orosco's life is finally in order. She married in December 2006. She turned 60 just a few days ago. Her son, Drew, is now 32.

But one lingering question remains: Who killed her 14-year-old daughter, Tina, nearly 24 years ago?

Orosco, who until 2006 was called Shirley Faelz, hopes that maybe now someone will be willing to come forward with information about her daughter's death.

"She's still in my heart," she said. "I still think something is going to come about."

Tina Faelz, then a freshman at Foothill High School, was last seen alive about 2:25 p.m. April 5, 1984. She was walking home from school and decided to take a route under Interstate 680 through a dark drainage culvert.

Less than an hour after she walked into the culvert, other students found her body on the other side of the freeway. She had been stabbed about 15 times in her back, face and side, police detectives said.

"It was a very thorough investigation," said Pleasanton police Lt. Darrin Davis, who took part in the investigation several months after the slaying. "The case file is several inches thick. All of her friends and associates were interviewed."

A $25,000 reward was offered but led nowhere. DNA evidence was recovered but testing did not exist at the time. There were no fingerprints, police said at the time.

The girl's mother told authorities

that a day before Tina was killed, she came home much later than usual and had asked to take karate lessons. That tip led police nowhere.

In the 1980s and'90s, police investigated two other convicted killers to determine if either killed Tina. She was the second of four young girls — along with Kellie Poppleton, 14, of Fremont, Lisa Monzo, 18, of San Lorenzo and Julie Connell, 18, of San Leandro — slain within several months of one another.

In 1994, DNA samples led authorities to charge 35-year-old Michael Ihde with Monzo's murder. He was convicted and sentenced to die in 1997. At the time, Ihde already was serving a life sentence in a Washington state prison for killing another woman.

Ihde was named as a suspect in the case at the time and has not been eliminated from the list of persons of interest, Davis said.

"But we have no information linkinghim to the homicide," Davis said.

In 1999, police investigated any possible connection between Tina's slaying and James Anthony Daveggio, who in 1997, along with his girlfriend Michelle Michaud, kidnapped, sexually assaulted and killed Vanessa Lei Samson of Pleasanton.

"We held meetings with the FBI, and there must have been 40 or 50 agencies there sharing information," Davis said.

However, no firm connection to the Faelz slaying could be found.

Davis said there are several persons of interests, including "convicted killers," as well as several others that have never been made public.

The homicide investigation is now inactive but has been opened five times in recent years, he said. Most recently, several DNA tests were run in 2007, but were inconclusive.

Detectives have traveled to other states several times to interview people, Davis said.

Orosco described her daughter as independent and mature for her age. She enjoyed playing soccer, baby sitting and riding her bike.

"I've gone through a lot," she said. "My life is now very fulfilled."

She said she doesn't think about the killer often, but still wants him or her to be held accountable, and to ask "why."

Drew Faelz lives in Sacramento. He is married and has two children of his own: Benjamin, 3, and Chloe Marie, 10 months. His daughter has the same middle name, Marie, as Tina.

"She was my big sister, someone I really looked up to," he said. He was 8 at the time of the slaying, and said he is still looking forward to some closure.

"Somebody out there must know what happened," he said.

Roman Gokhman can be reached at 925-847-2164 or rgokhman@bayareanewsgroup.com.