Doctors diagnosed Amber's problem as restrictive cardiomyopathy, a mysterious, irreversible disease in which the heart muscle becomes enlarged and cannot relax. Cardiologists say Amber probably wouldn't have survived to adulthood without a heart transplant.
On January 14, 1994, Linda Rhea signed a document at the Mohave County Jail which made the Hugheses legal caretakers of her four children.
One month later, Amber died.
Much of what happened in the day before Amber's death remains in dispute.
Although Amber's genitals were caked with blood when she died, the main suspects in her death--Nancy and Lee Hughes, and their live-in friend, Frances Rogers--have said they never saw signs of sexual abuse.
Amber's two older brothers--who were 8 and 9 when Amber died--haven't pointed the finger at anyone.
Nancy's son, Christopher, who was 7 at the time, also added little of substance. In the investigation's initial stages, police did not eliminate Christopher as a suspect, especially after hearing from the Bass boys and Lee Hughes that he'd hit Amber on several occasions. Detectives say their prime suspects now all are adults.
The Hugheses' daughter, Cassie, told a chilling story during a June 1995 talk with Phoenix therapist Tascha Boychuk.
Then 4, Cassie had been living in foster care since Amber died. After a time, she started to open up with her foster mother about Amber's death, which led to the session with Boychuk.
Cassie told the therapist that her father had "shot" Amber in the crotch with a gun. Authorities speculate Cassie may be referring to Amber's possible sexual assault with a gun barrel. By several accounts, Lee Hughes owned at least one gun in February 1994, though police found no weapons when they searched the Hughes apartment.
Boychuk asked Cassie to demonstrate with a doll if and where she saw blood on Amber.
". . . So you're pointing between the doll's legs here, okay," Boychuk said. "Where was the blood going?"
"Between her legs."
"So Amber was bleeding there, and who cleaned up the blood?"
"My mom Nancy . . . she put it right in the washer."
"Did anybody tell you not to tell?"
"Who was it that told you not to tell?"
"Uh, Nancy and my daddy."
Cassie's statements seem to incriminate her parents, Nancy and Lee Hughes. But it's uncertain if the courts would deem a child who was 3 years old when Amber died competent to testify.
Shortly before Amber's death, Nancy and Lee Hughes faced eviction from the Oasis Apartments. The landlord cited tardy rental payments, excessive noise, people coming and going at odd hours.
After Linda Rhea's kids moved in, nine people lived in the Hugheses' cluttered two-bedroom apartment.
Frances Rogers at the time was estranged from her husband and four children. She was a chronic meth user, and admitted to police in March 1994 that she'd last taken the drug a few weeks earlier--around the time of Amber's death.
The three boys and Amber slept in one room, with Amber assigned to a makeshift bed on the floor. Rogers slept on a couch.
On February 4, 1994, the Hugheses took Amber to a pediatrician because she had a cough and fever. The doctor diagnosed the child with viral pneumonia, but didn't consider her ill enough to need hospitalization.
A few days after that, Nancy Hughes spoke with Amber's heart specialist, Dr. Robert Williams. The doctor said he reminded Nancy how essential it was that Amber take her medicine twice a day.
On the evening of February 13, 1994, Nancy gave the children heart-shaped boxes of candy as Valentine's presents. Amber had missed the previous week of school because of illness, but planned to attend her kindergarten class the next day, a Monday.
Linda Rhea says she spoke to Amber that night in a phone call from jail.
"Everything seemed to be okay," she recalls. "I asked Amber how she was feeling. She said fine. She said she wanted the police to let me out so I could be with her. Me and Amber were very, very close. Why didn't she say something to me about how sick she was, that someone was doing bad things to her? But, now, I realize that Lee or Nancy or someone was right there when she was talking. Maybe that's why she didn't say anything."
The children went to bed about 8:30 p.m.
One of Amber's brothers says she began making "moaning, screaming and crying noises" soon after retiring. Nancy Hughes repeatedly implored the child to be quiet.
"I'm trying to be quiet," Amber's brothers say she responded loudly.
Probably before midnight, Nancy led the child to a living-room couch, then returned to bed. Lee Hughes--who had been sleeping--arose around 11:30 p.m., he told detectives, to the sound of Amber's coughing and whining.