Sandy Hook Group Releases PSA on Gun Violence

The video comes just before the 4-year anniversary of the inexplicable tragedy.

Meanwhile, another student exhibits several of the identified warning signs for violent behavior. The PSA is intended to make viewers aware of how easy it can be to overlook -- or do nothing -- about warning signs that often come before acts of violence.

“The ‘Know the Signs’ campaign has been our mission at Sandy Hook Promise for a number of years now. We believe that gun violence is preventable when you know the signs, when you know what to look for,” Nicole Hockley, the co-founder of Sandy Hook Promise, a national gun violence prevention organization, told ABC News.

“This has been the case in a number of mass shootings,” Hockley said. “It was the case of the shooting that killed my son.”

Since her son, Dylan, was killed at his school nearly four years ago in Newtown, Connecticut, Hockley said she has dedicated a majority of her time to trying to prevent gun violence and making sure no other mother has to suffer the same loss.

Hockley said all of the work she does now in memory of Dylan, who was only six years old when he was killed. “I can't go back in time and save Dylan but in his name we can save a lot of other people,” Hockley said.

Hockley described her son as "incredibly loving."

“He loved playing with other kids. He was fascinated by looking at the moon every night,” Hockley said. “He was pure love really.”

“Like a lot of children on the spectrum, communication was a challenge with him, his language skills were underdeveloped but all he did was love, that’s all he could express,” Hockley said.

The PSA comes out nearly four years after the tragedy at Sandy Hook Elementary School, which garnered many immediate calls for reform or action to prevent such a tragedy from ever happening again. Yet just this summer, Orlando was rocked with the deadliest mass shooting in U.S. history at a nightclub.

“We really hope that it is an eye opener,” Hockley said of the new PSA, adding that they have created a guide and a website so people can learn what the warning signs are, and become trained to prevent gun violence.

“In a little under two years we trained a little over 1 million people,” Hockley said, adding that they were made aware that their training program prevented a school shooting plot in Cincinnati.

Hockley said if her son were still around, she hopes he would be proud of the work she is doing.

“He’d be ten now, I think he’d have an understanding of what I do,” Hockley said. “I hope he’d be proud of me, and know that his legacy is giving so many other people a chance at life.”

“I just want people to watch this video, it is a compelling video I want them to know that there are actions that they can take in their own community, in their own family, to make a difference. All the training we provide is completely free. We just want to save lives.” she added.