Independence Day fireworks, once joyous celebrations, are now nightmares for these gun violence survivors

Gun violence can lead to life-long trauma that can even develop into post-traumatic stress disorder (PTSD). This is a psychiatric disorder that occurs in people who have experienced or witnessed a traumatic event like a shooting, natural disaster or abuse, according to the American Psychiatric Association (APA).

"Those triggers are really idiosyncratic, for some people it'll be a sound, for some it'll be a smell, for some it'll be like a voice," said Sonya B. Norman, director of the PTSD Consultation Program with the National Center for PTSD.

There are about 8 million people in the US diagnosed with PTSD, said Leah Blain, clinic director for the Steven A. Cohen Military Family Clinic at the University of Pennsylvania. Though there are groups who are disproportionately affected, the condition does not discriminate and includes symptoms like trouble sleeping, avoiding areas that can be a reminder of trauma and being in a constant state of alertness.

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