"I was picking up my children up from a preschool program at Winnetka Community House late morning, and all of a sudden I heard sirens going off all over the place, something really tragic must have happened," Margaret Vernon.
Margaret Vernon remembers when Laurie Dann opened fire inside Hubbard Woods School in Winnetka, killing a young boy and injuring two girls, in 1988.
Abby Adam's daughter, Hannah, was 8. She got a call from her husband that there had been a shooting and rushed to the school, not knowing if Hannah was hurt or dead. She wasn't injured, but saw the children who were.
"She has never gotten over it, when she hears a balloon pop, or hears fireworks," Adams said. "It comes right back to them, they are there."
Adams said she is also triggered by sirens that go blaring by.
That shooting changed Winnetka- and security procedures across the nation.
"Also I had children going to central school in Wilmette and immediately the school was locked down," Vernon said.
Vernon now lives across the street from Hubbard Woods School, where she sent three children.
"All of a sudden they couldn't come home for lunch anymore. You had to actually be walking over to pick them up," Vernon said.