Post-traumatic stress disorder (PTSD) is a sometimes debilitating mental health condition that appears in the weeks following an overwhelmingly stressful life event. At one point, this disorder belonged to a larger group of conditions called anxiety disorders; it now belongs to a group of conditions called trauma- and stressor-related disorders. While most people probably associate the onset of PTSD with events that occur in adult life, teenagers and younger children actually develop the disorder with some regularity. When it appears in teens and younger kids, PTSD can manifest in ways that differ significantly from the form of the disorder that appears in adults. Potential Causes As a rule, both children and adults develop symptoms of post-traumatic stress disorder in the aftermath of events that have the potential to cause fatalities or produce serious bodily injuries. In children and teenagers, the most likely forms of these events include physical or sexual abuse, car accidents and exposure to floods, fires or other disasters. Additional potential causes include violent situations on school campuses, witnessing domestic violence within the household, witnessing or experiencing violence in one\u2019s local community, abductions and exposure to war or acts of terror. According to Lucile Packard Children\u2019s Hospital at Stanford, factors that increase a teenager\u2019s or younger child\u2019s chances of developing PTSD in the aftermath of these events include recurring exposure to trauma, close-up experience of a traumatic event, the length and intensity of a traumatic event, and the individual\u2019s personal relationship to the people involved in a traumatic event. Frequency Roughly 5 percent of all US teenagers between the ages of 13 and 18 develop post-traumatic stress disorder, according to figures compiled by the US Department of Veterans Affairs\u2019 National Center for PTSD. Risks for the disorder in this age group are more than three times higher for females than for males. Generally speaking, the risks for both males and females rise as teenagers grow older. No one has systematically studied the rates for PTSD in preteens and younger children; for this reason, no one knows for sure how many children in this age group develop diagnosable symptoms of the disorder. Manifestations in Younger Children In adults, PTSD typically manifests in symptoms such as emotional numbness, amnesia, or avoidance of things that trigger memories of a traumatic event, an unwanted re-experiencing of a trauma through nightmares or flashbacks, and an unusually vigilant, alert or jumpy state of mind. Younger children with PTSD sometimes don\u2019t develop amnesia or flashbacks, the National Center for PTSD reports. Instead, they re-order the sequence of traumatic events in their minds or develop a mistaken belief that they missed certain warning signs that could have alerted them to the source of their trauma exposure. Younger children affected by PTSD may also feel a compulsion to relive specific facets of their experiences. Manifestations in Teenagers Since teenagers are closer to adulthood, their PTSD-related symptoms align with adult symptoms of the disorder to a considerable degree. Still, while adults with PTSD tend to forget key details of traumatic experiences or relive their experiences through flashbacks, teenagers tend to participate in something called post-traumatic reenactment. During post-traumatic reenactment, an affected individual will start engaging in behaviors that mimic some feature of a traumatic event. For instance, a teenager exposed to gunfire might suddenly start carrying a gun. Considerations Since teenagers and younger children frequently develop post-traumatic stress symptoms that don\u2019t correspond with the standard criteria for diagnosing PTSD in adults, doctors sometimes miss or misinterpret the effects of trauma exposure in these population groups, according to the results of a study review published in 2005 by the University of Illinois at Chicago. As a consequence of this misinterpretation or misdiagnosis, the presence of PTSD harms the normal development of significant numbers of children and teens. The National Center for PTSD lists several forms of psychotherapeutic treatment that are appropriate for teens and younger children affected by PTSD. They include cognitive behavioral therapy, which involves a relearning of habitual responses to stressful circumstances; psychological first aid, which involves such things as comforting trauma sufferers and identifying people who need further care; and play theory, a technique used to help young children process their traumatic experiences when they lack the mental\/emotional maturity to face those experiences in a more conscious way.