BBC News (bbc.com) reports a study where nearly a third of 18 year olds had experienced childhood trauma. 25% of them developed symptoms of Post Traumatic Stress Disorder (PTSD), including insomnia, flashbacks, avoidance, guilt, irritability, impulsivity, difficulty concentrating, and feelings of isolation. The BBC article notes that many people wrongly think PTSD only affects people in the military. It goes on to describe a young woman who developed PTSD as a result of surgery she endured as an infant. "People don't really associate PTSD with a young child - and that has to change," she said.
Here's the full article: https://www.bbc.com/news/health-47317891