Updated

For weeks, Erica Lynn Parsons' brown eyes and smiling face have gazed out upon residents of this central North Carolina community from posters, leaflets and billboards.

In one photo, she appears as a young elementary school-aged child and in another, thanks to age-progressing computer technology, as a 15-year-old.

No one is sure exactly how long Erica has been missing. When her 20-year-old brother reported her disappearance on July 30, he said she actually had gone missing a year and a half before that.

Concerned residents have held candlelight vigils during which they have begged anyone with information about her whereabouts to come forward.

"We're hoping for the best," said Alan Carpenter, a Salisbury resident who lives near Erica's family and attended a recent vigil at the Rowan County Courthouse. "But we just don't know. There are just too many unanswered questions."

For their part, law enforcement authorities are starting to think Erica won't be found — at least not alive.

Investigators with the Rowan County Sheriff's Office say Erica's adoptive parents have been uncooperative and that they have uncovered disturbing signs of foul play. No charges have been filed, however.

Erica was adopted in 2000, when she was just 2 years old, by her uncle and aunt, Sandy and Casey Parsons. The Parsonses say they haven't seen Erica since late 2011, when they say she moved to Asheville, N.C., to live with a woman they believed was her biological grandmother.

But police say they've been unable to locate the grandmother. Casey and Sandy Parsons "were unable to provide any known locations" or contact information, officers wrote in one of two affidavits seeking warrants to search the Parsonses' house and a shed on property owned by Sandy Parsons' father.

Law enforcement officials have declined to discuss details of the investigation. The Federal Bureau of Investigation is assisting the sheriff's office.

The Parsonses recently moved from their Salisbury home about 40 miles north of Charlotte to the Fayetteville area to escape news media attention. Their attorney, Carlyle Sherrill, told The Associated Press his clients had nothing to do with Erica's disappearance.

"They want her back home," he said.

The search warrant affidavits filed by police paint a picture of a young girl isolated from the outside world who may have been mentally and physically abused by her parents.

"Family members stated that Erica always seemed to be 'grounded' and never allowed to interact with the family," once being beaten so hard with a toy gun that it broke into pieces, a sheriff's office investigator wrote.

Witnesses told police that Casey Parsons, 38, and Sandy Parsons, 39, physically abused Erica, who "consistently had bruises and bumps on her arms and legs," the investigator wrote.

Sherrill, the family's attorney, said social workers investigated reports of child abuse in the Parsonses' home on four different occasions in recent years.

"But none of them were substantiated as far as beating the kids or abuse," he said.

From the beginning, Erica, whom witnesses and Sherrill described as a shy, quiet girl, was surrounded by people who didn't seem to want her.

Just two weeks after she was born on Feb. 24, 1998, her biological mother, Carolyn Parsons, who was married to Sandy Parsons' brother, told her in-laws she couldn't take care of her baby.

The Parsonses, who had three children of their own, agreed to take Erica, and later adopted her.

But when Erica was 6, they sent her to live with another family member, an investigator said in the affidavit for the search warrant. That family member, who was not identified, said Casey told her she beat the girl because she "couldn't stand to look at Erica."

Eight months later, Sandy and Casey Parsons took Erica back because they were afraid they'd lose the state money they were receiving to help with the child's learning disability and hearing problems, the investigator wrote.

Witnesses not related to the family said it was dysfunctional, mainly due to problems the parents were having with James, the same son who later reported Erica's disappearance.

According to Sherrill, Casey Parsons battled gastrointestinal issues for years after botched gastric-bypass surgery. By 2011, she was very sick, and James "took out his aggression on his mother," the attorney said.

James was charged with assaulting his mother and a sibling, and animal cruelty, Sherrill said. It was during this period that Casey Parsons began to wonder what would happen to her children if she died, he said.

In July 2011, the Parsonses re-introduced Erica to her biological mother, but Erica told them she did not want to live with her, Sherrill said.

A few months later, according to the lawyer, Casey and Sandy Parsons said they were contacted by a woman on Facebook who claimed she was Carolyn's mother and Erica's grandmother. She said her name was Irene or "Nan" Goodman, Sherrill said.

"Nan knew all about their family, all about the names of the children," Sherrill said. "Nan tells them that she learned that through Carolyn."

The Parsonses said they arranged a meeting with "Nan" at a fast-food restaurant in September 2011. They let Erica spend a weekend with the supposed grandmother in her Asheville home, and later allowed her to go on a three-week trip with Nan in December 2011, Sherrill said. It was during that trip that Erica called to say she was happy and wanted to live there, he said.

Sherrill said the family agreed because Casey Parsons was still sick and James Parsons was continuing to misbehave.

The Parsons family then lost touch with Erica, but assumed she was safe, Sherrill said. "The phone number they had for Nan didn't work anymore," he said.

In June, Casey and Sandy Parsons kicked James out of the house after he assaulted Casey, Sherrill said.

A month later, James Parsons walked into the sheriff's office to report that his sister had been missing for nearly a year and a half and that his parents had been abusing her for years.

The next day, the Parsonses' two youngest children were removed from the home by the Rowan County Department of Social Services pending an investigation.

The couple told police that Erica was with Nan. They repeated the same story to the local news media and later on a nationally syndicated TV talk show.

But during police questioning, Casey Parsons often referred to Erica in the past tense, an investigator wrote in one of the search warrant affidavits.

"I found these statements to be inconsistent," since the family claims to have left Erica "alive, well, and happy with her biological grandmother," the investigator wrote.

Meanwhile, police pressed ahead with the investigation, but could find no evidence that Irene "Nan" Goodman ever existed.

On Aug. 14, investigators removed more than a dozen items from the family's house, including pieces of wall stained with what appeared to be blood and two knives encased in shrink wrap, according to one of the affidavits.

They also found books and magazine articles about JonBenet Ramsey, a child beauty queen found slain in her Colorado home in 1996; and Susan Smith, a South Carolina woman who killed her two children in 1994. Seized financial records showed that the Parsonses continued collecting money from the state even after Erica disappeared, according to the affidavit.

While the investigation continues, the National Center for Missing & Exploited Children has erected more than a dozen billboards featuring Erica's picture around the Charlotte area.

"They are all reminders that something bad happened," Carpenter said. "Everyone wants this to end well. All we can do is pray."