According to the National Child Traumatic Stress Disorder, Pediatric medical traumatic stress refers to reactions that children and their families may have to pain, injury, and serious illness; or to "invasive" medical procedures (such as surgery) or treatments (such as burn care) that are sometimes frightening. Reactions can affect the mind as well as the body. For example, children and their families may become anxious, irritable, or on edge. They may have unwanted thoughts or nightmares about the illness, injury, or the hospital. Some people may avoid going to the doctor or the hospital, or lose interest in being with friends and family and in things they used to enjoy. As a result, they may not do well at school, work, or home. How children and families cope with these changes is related to the person's own thoughts and feelings about the illness, injury, or the hospital; reactions can vary, even within the same family.