1. Susan Hatters Friedman, MD* 2. Joshua B. Friedman, MD, PhD† 1. *Senior Instructor in Psychiatry and Pediatrics, Case Western Reserve University School of Medicine, Cleveland, Ohio; Consultant Forensic Psychiatrist, Mason Clinic, Waitemata District Health Board, Auckland, New Zealand. 2. †Fellow in Child Protection Paediatrics; Te Puaruruhau Child Protection Unit, Auckland District Health Board, Auckland, New Zealand. After completing this article, readers should be able to: 1. Identify commonalities among women who commit neonaticide (killing the infant in the first day after birth). 2. Describe commonalities among parents who kill their children for reasons related to parental mental illness. 3. Delineate the role of the pediatrician in the detection of both denial of pregnancy in teenagers and of parental depression and psychosis. 4. Discuss potential strategies for preventing parents from killing their children. Child homicide is a significant public health problem in America. In 2005, homicide was the fourth leading cause of death in both the 1- to 4-year-old and 5- to 14-year-old age groups. (1) Most young children who are homicide victims are killed by a parent. Of American children younger than 5 years of age who were murdered over the 30-year period from 1976 to 2005, 31% were killed by their fathers or stepfathers, and 29% were killed by their mothers or stepmothers. (2) Of the 40% not killed by a parent, most were killed by male acquaintances. The average number of children up to 5 years of age known to be murdered by their parents in the United States was 344 per year (range, 246 to 426). (2) Underestimations of death rates, however, pervade the literature. There are hidden pregnancies and hidden corpses, medical examiner misjudgments of homicide as being accidental or natural (eg, sudden infant death syndrome) or undetermined, and unwillingness to place responsibility on a grieving parent. (3) In addition, estimates of the frequency of maltreatment and death vary, depending on the data source. Filicide is defined as the homicide of a child by …