CHARLOTTE, N.C. -- A Charlotte security group, Saf Technologies, planned a local event about active shooters weeks ago-- long before Wednesday''s mass shooting.
The keynote speaker is the teacher who saved her students at Sandy Hook by hiding them all in a bathroom.
Kaitlyn Roig DeBellis really couldn't believe it was happening again.
"It's just mind boggling to me that this continues to happen and my heart just breaks."
Wednesday's mass shooting is the deadliest since Sandy Hook-- the Newtown elementary school where Kaitlyn squeezed her 15 first graders into a tiny bathroom, saving their lives.
"I did what any teacher would have done," she tells NBC Charlotte. "Those kids are my responsibility-- in the six hours they're in school with me, they're my babies. I'm they're protector. I wanted us to survive and so our only option was hiding and that's what we did."
In her book, Choosing Hope, she writes about squeezing everyone in to the three-by-four foot bathroom as they heard bullets just outside.
"I had never been in it until that day. It was way too small for a grown adult to comfortably fit, but in that moment the impossible needed to become possible for us."
She says hearing about mass shootings so often is painful, but she has advice for the worst case scenario: Trust your instincts and be aware.
"Awareness of our surroundings, where you are whether in school building, where are your exits, being resourceful."
And she says while you never move on from something like Sandy Hook-- or San Bernardino, you can move forward by choosing hope.
"It's a choice and it's not the easy one."
