Now, the Marjory Stoneman Douglas community is mourning yet another loss.
Sydney's mother, Cara Aiello, told CBS Miami that her daughter struggled with survivor's guilt and was diagnosed with post-traumatic stress disorder in the year following the tragedy. And while she reportedly never asked for help, she struggled to attend college classes because she was scared of being in a classroom.
Sydney was also a close friend of Meadow Pollack, one of the students who was shot and killed in the Parkland shooting. Meadow's father, Andrew, became one of the most visible of the Parkland victims' parents when he delivered a searing and emotional speech at the White House just a few days after the shooting, arguing for an increase in school safety rather than changes to America's gun laws.
CBS News journalists embedded with Andrew Pollack as part of the documentary "39 Days", which showcased the birth of a movement as many Parkland students turned their grief into action.
While the nation's attention turned to budding young activists like David Hogg and Emma Gonzalez, however, other Parkland survivors were suffering in silence. And the Aiello family's tragedy is an all too painful reminder that trauma effects teens deeply, often quietly, and for years.
Ryan Petty, whose daughter Alaina died in the shooting, told CBS Miami he worries that more traumatized Parkland teens will take their own lives. So, he has focused his grief and his efforts into suicide prevention.
"Sydney spent 19 years writing her story as a beloved daughter, sister and friend to many," the page reads. "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. It was a privilege to have you in our lives. Sydney, we will miss you and always love you. May you find peace in His arms."