This fact sheet provides data on infants, toddlers and young children who are experiencing high stress as a result of a number of risk factors specifically identified in the Individuals with Disabilities Education Improvement Act of 2004 (IDEA 2004), including substantiated abuse or neglect, foster care placement, homelessness, exposure to family violence and prenatal exposure to drugs or alcohol. It should be noted that these risk factors often co-occur with other serious risk factors, such as extreme poverty, environmental toxins, parental substance abuse (post-natally), and parental mental health problems, especially maternal depression.