Police say Alicia and Steven Kelly won the sympathy and financial donations of friends and strangers, telling them their 15-year-old daughter suffered from bone cancer.
But the person they exploited the most was their own teenager, convincing her that she had a deadly disease by giving her blood pressure pills and telling her it was her "chemo medicine," according to police in Greenwood County, S.C.
And that wasn't all, they say.
The couple, who were responsible for looking after her elderly father, allegedly neglected his care, leaving him to die in a trailer while they collected his Social Security checks for 18 months, allege police.
The Kellys -- 38 and 39 years old respectively -- spent the last two years lying to their community and their children, saying they did not have enough money to treat their daughter's disease, said police.
Efforts by ABC News to reach the Kelly family were unsuccessful.
"They were doing two scams at the same time," said Major John Murray of the Greenwood Sheriff's office. "There is not much difference than somebody going out and robbing somebody with a gun. What they did was instead of using a gun to rob people, they used sympathy to rob people. It's the same difference. One plays off of fear and one plays off of sympathy."
"A few months into it, the daughter figured out she didn't have cancer," according to Murray, who said police were eventually tipped off and arrested the couple on five fraudulent check warrants on Feb. 4.
"The girl's parents had gone to churches and different community groups to raise money, including the American Cancer Society's Relay for Life, according to Murray.
Joining the website Caring Bridge to gain sympathy and donations, the family chronicled their daughter's bogus illness with "58 pages written on how sick she was," he said. There are four other children in the family, aged 13, 12, 3 and 2.
"It's a tragedy, especially for the children," said Murray. "This is something they will have to deal with for the rest of their lives."
Psychologists and child development experts agree that exploiting a child who has a parents' ultimate trust can have devastating consequences, including depression or suicide if she is not emotionally stable enough to weather the storm.
"We can be looking at serious post-traumatic stress," said Anthony Siracusa, a clinical psychologist from Williamstown, Mass., who specializes in families and child abuse. He has not treated the Kellys' daughter.
"A diagnosis of cancer, as we can all imagine, is earth-shattering," he said. "To think your life and longevity has been questioned."
Siracusa said the girl might also develop a fear medical treatment. "Even if she is cognitively wise enough, she may not be emotionally."
"It could have an impact on how she cares for herself in the future, or the ability to care for children as a parent," he said. "She may have some real serious problems."
Teen in Alleged Cancer Scam Needs Support
Siracusa said authorities should ensure that the teen gets support, not only from relatives, but from professional counseling.
Police said that the girl, whom they would not identify because she was a minor, is now living in Greenwood with her paternal grandparents and her other siblings.
Social services is providing financial support, food and counseling for the family, they said.
The children had only been in school for three out of the last five years, according to police, and were placed with family, rather than with social services agencies, to provide some stability.
"She may blame herself or feel in some strange way that she is responsible, but it needs to be clear that she was a victim in this," Siracusa said.
How the teen will fare depends on "what strength she has had handling crises in the past," said Siracusa. "It's hard to say what kind of self-esteem or self-awareness she has, and what people do now to support her will make a big difference."
Murray said they got involved in the case when they heard "rumors about there being a scam going on."
Police said they did background checks with agencies to find out if the girl was getting cancer treatments.
Murray said police asked the state Department of Health and Environmental Health Control to pull the girl's medical records and found she was not on any cancer drug treatment. Alicia Kelly was apprehended after a warrant was issued, accusing her of issuing a bad check, he said.
"We picked her up on that and brought her in," said Murray. "We went through the interrogation in the cancer scheme and after about four or five hours, she broke and confessed it was all a scam."
The next morning, upon further interrogation, police learned some of the checks were in Kelly's father's name and they suspected she might be stealing from his bank account.
"We asked her where he was so we could interview him, and she said he was dead in a local trailer out in the county and had been dead since November," said Murray. "We figured it was this year. When we conducted a search of the trailer we found a body on its side on the floor in a little camper trailer, about 35-feet long and the body was already mummified."
When police checked dated milk bottles in the house, they realized the man had been dead since 2009. There was no food in the cabinets, only an empty gallon of milk.
Police charged Alicia Kelly with neglect of a vulnerable adult that results in death, a felony that carries a 30-year sentence.
Both Kellys are charged with two counts of swindling for money, as well as claiming their daughter was stricken with cancer. They are also charged with three counts of contributing to the delinquency of a minor.
The various charges could -- at least on paper -- send the couple to jail for 100 years, according to Murray.
The Kellys had been "bouncing around," but at the time of their arrest, the husband had a job working at a local factory and the family was living in a local hotel, according to Murray. The couple had more than $5,000 cash on them.
The children in the Kelly family, as alleged by police, are a "prime example" of cumulative risk -- lack of education, social support and normalcy, according to Tasha R. Howe, associate professor of psychology at Humboldt State University in California.
"The severe neglect of an elder in the family is often tied to abuse or neglect of the children," she said. "Not only has the girl realized her illness was a lie, but the people who were supposed to love and protect her, her parents, have betrayed her... and now the only caregivers she has known have also been taken away from her."
"And even though only one child was used for the cancer scam, all of the other children are at equal risk for developmental problems."