Fred and Debbie McGraw remember their little girl as a happy child, good student, and all-star pitcher in Audubon.

They never envisioned that their daughter, Desiree, would drop out of school in the 11th grade and support her drug habit by hooking on the streets of Camden.

"They're going to find you one day dead in an alley, Desiree," her father warned as he tried to lure her home. His daughter, however, preferred Broadway, Camden's cold corridor filled with prostitutes, dealers, and a smorgasbord of drugs.

Instead of an alley, Desiree McGraw's partially clothed body was found four years ago behind the Jericho Fire Company in Deptford Township. The 27-year-old mother of two had been executed with a single bullet to the back of the head.

"I fell to my knees," Debbie McGraw said of the day she learned of her daughter's death while she was in Philadelphia undergoing chemotherapy for breast cancer.

With the arrival of the fourth anniversary, authorities raised a reward to $8,000, hoping to generate fresh leads to answer the questions that haunt relatives and friends: Who killed McGraw and why?

Investigators won't discuss motives or suspects in detail, but they say solving the case remains a priority in a county where homicides are few.

"She was a mother, a daughter, a sister, and a friend to many," Gloucester County Prosecutor Sean Dalton said. "She will not be forgotten."

The slaying was unusual for Gloucester County, where some years, such as 2008, pass without a single homicide. Victims there are more likely to be killed in domestic disputes than over drugs.

McGraw, who authorities believe was killed where her body was found, may have been shot over drugs, but Dalton said investigators had not ruled out other motives. Her family believes it had to be drugs, possibly for stealing from a dealer.

"She got mixed up with the wrong people, and they brought her down fast," said Jennifer McGraw, Desiree's older sister, who said she often went to Camden to pull her sister off the street.

Family pictures reflect a sad progression. In 1993, a young Desiree posed in a purple jersey for a softball portrait, an aluminum bat on her shoulder.

The last nice photo the family has is a 2001 portrait, her blond hair framing her blue eyes and a reserved smile.

That same year, officials captured the street-beaten expression of a convict, her hair pulled back in cornrows as she entered a state prison to serve a year and a half on a drug-conspiracy charge.

Her son, now 10, was taken away by state workers and eventually raised by his grandparents. Her daughter, now 4, was born addicted to drugs 27 weeks into the pregnancy.

"To this day, doctors say she is a walking miracle because she should not have survived," said Jennifer McGraw, who adopted the baby. "My sister kept saying, 'I want her back. I'm going to get my life together.' But that never happened."

Over time, her addictions included abuse of marijuana, crack cocaine, and heroin that she mainlined. McGraw had been arrested numerous times for drug offenses, disorderly conduct, and prostitution, her family said.

Debbie McGraw said she and her husband appealed to police to keep their daughter in jail, figuring she would be safer there than on the street. Each time, she was released within days, she said.

Fred McGraw last spoke to his daughter the Friday before her death. She called from jail.

"She said, 'I'm tired of this. I want to change my life,' " her father recalled. "She was dead by Monday."

The $8,000 reward offered by the Gloucester County Prosecutor's Office and the Deptford Township Police Department is for information leading to an arrest and conviction. Anyone with information can contact Detective James Ballenger of the Prosecutor's Office at 856-384-5601.