Two weeks before Devani's second birthday, she was taken away from her parents in Tucson by a state child-welfare caseworker. The little curly-haired girl seemed to be well-fed and cared for, but the caseworker cited drugs in the home and alleged domestic violence in deciding that Devani would be safer, at least temporarily, in foster care. Instead, over the next four years as her mother fought to get her back " Devani suffered an odyssey of mistreatment in a succession of foster homes. She was physically abused. She was placed with David Frodsham, a man subsequently convicted of child molestation, who investigators suspect repeatedly sexually assaulted her and other foster children while he ran a pedophilia ring. And that would not be the worst that Devani would face. Foster parents who harm children the state leaves in their care are tracked in only the broadest terms. The state handles verified allegations of neglect or abuse in foster families much as it does those in other families. But officials admit they don't really analyze the data for patterns of foster-care problems that could be prevented. And data shows caseworkers often don't talk privately with children to identify what happens to them in foster care. Those children's families say the problem is real. Of 42 families interviewed for this story who had children removed, 11 alleged that their children were physically or sexually abused, exposed to drugs or harmed in some other way while in foster care.