At first glance, Dr. Lucy Weiss looks like the typical high-achieving, upper-middle-class working mother who, along with her husband, is bringing up much-beloved children in a world of Saturday morning soccer, private-school teacher conferences, and hyperaggressive classroom mommies. But Lucy's own history makes her an anomaly. Having overcome a difficult childhood in foster care, she is what's called a super-survivor, a kid who grew up in the margins. Now a pediatrician, Lucy finds herself working with some of these same at-risk patients and their families.

The Mercy Rule is a novel about the all-important job of taking care of children. Lucy's work takes her back into the world of families living on the edge, where every day she must decide whether parents' actions are so incompetent - or so flaky - that their children are in danger. It's her job to make the call and to step in when she has to. As she moves between her disparate worlds - from worrying about her own brilliant but odd son being labeled with a diagnosis to worrying about parents struggling with drugs and impossible living situations - Lucy must judge herself as a parent, critique other parents, and also deal with the echoes of her childhood.

Watching Lucy try to keep the balance, enjoy her own children, and look at other families with humor and justice and mercy, readers will understand why Chris Bohjalian said of Perri Klass, "Few writers write as beautifully or as authentically about parenting."