"The sadness and distress are still there."

19-year-old Parkland school shooting survivor Sydney Aiello has died by suicide. The student was on campus at Florida's Marjory Stoneman Douglas High School when 17 people were killed by gunman Nikolas Cruz last year. Sydney was not in the freshman building where the former student carried out his attack, but her mother Cara said that since the shooting, her daughter had suffered from post-traumatic stress disorder and survivor's guilt. She died by suicide last weekend. "Sydney spent 19 years writing her story as a beloved daughter, sister and friend to many," reads a GoFundMe page set up in the teenager's honour.

"She lit up every room she entered. She filled her days cheerleading, doing yoga, and brightening up the days of others. Sydney aspired to work in the medical field helping others in need. "On March 17th, 2019 Sydney became the guardian angel to many."

Dr Victor Schwartz told NBC News that experiencing an event such as the Parkland shooting can put some survivors at risk of suicide. "It stands to reason that there is some increased risk around the survivor guilt," he said. "Parkland students have done an incredible job being out there and advocating for gun safety, but the sadness and distress are still there. I'm sure many of these students are still struggling with symptoms that look like PTSD. "And how could they not be?" Sydney was buried in Parkland this week.