A young child goes missing, and her parents are in despair.
They make heartfelt televised appeals for the return of their daughter, and the public sympathizes with their plight. But after a few days or weeks, the parents are questioned in the disappearance, the media reports on growing suspicions from anonymous authorities and the public becomes accusatory.
Whether it's the Ramseys, the Aisenbergs or the Smarts, these notorious cases of parents with a missing child seem to follow a similar trajectory, fueled by the media frenzy, as the public mood turns from empathy to suspicion.
Kate and Gerry McCann, the British couple who reported their 4-year-old daughter, Madeleine, missing from their resort hotel room in southern Portugal May 3, are just the latest example of victims turned villains.
Is this change in opinion unfair to the parents in these cases, a symptom of public cynicism and the media obsession with building up and then tearing down their idols? Or is it a reasonable reaction, given the fact that most homicides of young children are committed by their parents?
In the first few weeks, the McCanns' story attracted plenty of sympathy, with neighbors in Portugal putting up posters of Madeleine and Britons holding candlelight vigils praying for the girl's safe return.
But as the search turned up no trace of Madeleine and after her parents were named by police as suspects last week, prompting them to hire a high-profile lawyer, the mood quickly turned and the headlines became vicious.
"Did you kill her by accident" blasted the Daily Mail. "Madeleine: We Can Prove Parents Did It," blared the Daily Express. Even the Help Find Madeleine McCann Web site was flooded with spiteful comments from "I never believed your pain" to "You have shown nothing but cold emotion ever since 3rd May." Another Web site, organized by the McCanns' local newspaper, had to be shut down after it was bombarded with vicious comments.
In the latest twist, despite the fact that Portugal's national police chief deemed inconclusive forensic tests that purportedly found evidence of Madeleine's DNA in the trunk of a car rented by the McCanns five weeks after her disappearance, the public remains suspicious.
In a random sampling of Britons questioned by ABC News, none declared that the couple was innocent and many believed they were guilty of harming their daughter.
Perhaps those reactions aren't surprising considering the statistics on child homicide. Of all children under age 5 murdered from 1976 to 2005 in the United States, 60 percent were killed by their parents and only 3 percent were killed by strangers, according to the Justice Department.
"The younger the child, the more likely the parental involvement," says Robert D. Keppel, an associate professor of criminal justice at the University of New Haven and former chief criminal investigator for the Washington State Attorney General's Office. The results are different in the cases of children who are abducted and murdered, according to a study he conducted.
"Most of those abductions of children who are found murdered, most of them are abducted by people other than family -- neighbors, strangers, everybody else," he says. That makes sense, considering that parents who kill their children usually don't need to abduct them first.