MIAMI -- Rilya Wilson's disappearance four years ago scandalized Florida's child-protection agency, but prosecutors say they now know what happened to the 4-year-old and charged one of her caregivers with murder.

Geralyn Graham, who was supposed to be taking care of the foster child, confessed while in jail on unrelated fraud charges, Katherine Fernandez Rundle, Miami-Dade state attorney, said Wednesday. Investigators later found corroborating evidence, she said.

"She basically broke down and told someone in the jail details about Rilya Wilson, including how she killed her," said Fernandez Rundle, who declined to give details.

Local 10 News' Gwen Belton spoke to the lead detective, Sarah Tymes, about the alleged confession. The following exchange took place.

Tymes: "I cannot go into detail, verbatim, as to everything that was discussed in the confession of Mrs. Graham."

Belton: "But she did confess?"

Tymes: "Yes. She did confess to killing Rilya Wilson."

Belton: "And then doing what with the child?"

Tymes: "Disposing of the child."

Belton: "Where?"

Tymes: "In a ravine."

Graham was previously charged with kidnapping and aggravated child abuse covering the time before Rilya's disappearance. No body has been found, prosecutors said.

Graham is scheduled to be arraigned at 9 a.m. Friday in Miami-Dade County Circuit Court, officials said.

Graham's attorney, Brian Tannebaum, denied the charge.

"That's based on a jailhouse snitch," he said. "They have no other evidence."

Rilya's story became known three years ago when it was discovered that she was not living at the home she shared with Graham and another woman, Pamela Graham, who was Rilya's legal guardian.

The Grahams, who are not related, claimed a state social worker had taken the child in early 2001 for medical testing and never returned with the girl, who was 4 when she was last seen.

The girl's disappearance had gone unnoticed by the Florida Department of Children & Families for months. The scandal led to a major shake-up at the agency, as well as a search for the girl.

Prosecutors refused to give details on how they determined to charge Geralyn Graham, and the indictment doesn't mention any evidence. The indictment did allege, however, that Rilya was either suffocated or beaten to death sometime in December 2000.

Tannebaum said, "This is a woman who they charged with kidnapping without any evidence that she took the child anywhere and now they've charged her with the murder of a child they have not located."

Graham is in jail on unrelated fraud charges and could have a court appearance as early as Thursday on the new charges, said state attorney spokesman Ed Griffith. The fallout of Rilya's disappearance was immediate.

A blue-ribbon panel appointed by Gov. Jeb Bush to investigate Rilya's disappearance found massive problems at DCF, including the failure to check the background of caregivers and low pay for child protection workers.

DCF Secretary Kathleen Kearney resigned in September 2002 and seven of 14 regional administrators with the agency were replaced. The Legislature passed a law making it a felony for welfare workers to falsify documents relating to anyone in state care.

Geralyn Graham was arrested shortly after the disappearance on unrelated charges and was convicted of using a friend's Social Security number to buy a sport utility vehicle. She got three years in jail, where she remains. Pamela Graham pleaded guilty to accepting welfare payments for Rilya after the girl left her care and received two years' probation.

But no charges were filed for Rilya's disappearance until August when Geralyn Graham was accused of aggravated child abuse, for locking Rilya in a cage and other alleged mistreatment. She was also charged with kidnapping for removing Rilya from Pamela Graham's custody. Pamela Graham, who was cooperating with authorities, was charged with child abuse.

Rilya was born Sept. 29, 1996, to a homeless cocaine addict. The girl's name was an acronym for "Remember I love you always." She was taken into state custody when she was less than 2 months old.

In April 2000, when she was 3, Rilya was placed in the custody of Pamela Graham. The Grahams have called themselves sisters, but Pamela Graham told co-workers that Geralyn was her wife. Geralyn Graham told The Miami Herald in August that she and Pamela had been in a "loving" but nonsexual relationship for 10 years.

DCF later acknowledged that its background check had failed to discover that Geralyn Graham had a long criminal history for fraud and had been diagnosed as psychotic six months before Rilya moved in.