Nicole Hockley, whose son was killed at Sandy Hook, reflects on all we've lost and what we still stand to change.

The last decade has been one of the deadliest in U.S. history in regard to gun deaths. More parents are losing their children to gun violence than ever. Last year alone, American schools experienced the most shootings on record — 116 — and we are keeping that pace in 2019.

Too many families have to endure the pain of burying their child, having to walk through life knowing a part of them is forever missing. It’s a dark and lonely tunnel almost impossible to endure. Families know this pain in Parkland, Florida (2018); Marysville, Washington (2014); Santa Fe, Texas (2018); and too many other school communities across the country. Looking beyond schools to other mass shooting events, families know this pain in Aurora, Colorado (where 12 people were killed in a movie theater, 2012), Orlando (49 people in a nightclub, 2016), Las Vegas (where 58 people were killed and 413 wounded at a music festival in 2017). Communities affected by the several church, synagogue, and mosque shootings in the last decade carry this pain.

I, too, carry this pain with me every day. Seven years ago, on December 14, 2012, I put both of my sons on the bus, not knowing that only one would return. That day, my son Dylan was murdered, along with 19 of his first-grade classmates and six educators at Sandy Hook Elementary School.

Every time I hear about another shooting, I think about the families whose lives will be changed forever — a single moment that will define the rest of their life just as it has defined mine.

But there is hope.

Out of all the tears, tragedy, and loss, we’ve learned an important lesson: gun violence is preventable when you know the signs.

After my son was murdered, experts spoke about the warning signs that were missed. If only someone had said something and intervened when seeing those signs, my beautiful butterfly Dylan might still be with us today.

Research consistently shows that school shooters exhibit at-risk behaviors prior to carrying out an attack — from outright threats and patterns of impulsive behaviors like chronic hitting, or bragging about a weapon, to bullying and/or withdrawing from their peers. We need to know these signs, empower people to say something when they see them, and intervene before students have the chance to hurt themselves or others. That’s how we can prevent more tragedies from happening.

When I was told there weren’t any national programs in place to teach these signs and how to act on them, I vowed Sandy Hook Promise would fill that void. We worked with educators, psychologists, and threat assessment experts to create a series of programs that empower students to protect their school community.

A recent report from the U.S. Secret Service supports this approach, concluding that early intervention is the key to prevention. They reinforced that a more multi-pronged approach is needed, including central reporting systems that protect anonymity, creating a culture where students are encouraged to share their concerns, and providing training on the warning signs for students, educators, and parents.

Since its launch last year, students trained in the Say Something program have submitted more than 40,000 tips through school- and state-based Anonymous Reporting Systems. These tips include potential school shootings, domestic violence, bullying, cutting, substance abuse, suicide, and more — and have resulted in countless life-saving interventions. Sandy Hook Promise just announced that 11 million students and educators have participated in one or more of the Know the Signs programs since its inception in late 2014. Through these no-cost programs, we’ve averted multiple school shooting plots, teen suicides, and countless other acts of violence.

It’s too late for me and too many other families, but these interventions give me hope and keep me moving forward. I believe we will look back and see this time as a turning point: the time when we learned to become upstanders and take action to intervene, rather than remain passive bystanders allowing tragedies to unfold.

People say nothing has changed since my son was murdered. I don’t agree.

Gun violence prevention has become a national movement, with many millions of supporters. It’s a primary topic in political campaign conversations, rather than the “third rail” or too controversial. There have been significant legislative changes in dozens of states, including the implementation of Extreme Risk Protection Orders and Background Checks, with additional policies being discussed at a federal level.

The biggest reason I believe we are at a tipping point is because we are training students. After the Parkland tragedy, student voices and calls for change bloomed. These persistent calls were echoed by students in thousands of nationwide clubs supporting Sandy Hook Promise. This is a generation that grew up with school shootings, gun violence, and active shooter drills, it shouldn’t be surprising that this will be the generation to change our unacceptable status quo.

Lives are being saved. Legislation is gathering support. And the movement and demand for meaningful change continues to grow.

While there is hope that this is truly a turning point, we also can’t be complacent. We have to keep our promise and do everything we can to protect children from gun violence. The last decade may be remembered as one of the deadliest in history for American children. Let’s make sure the next one is remembered for remarkable change.

Nicole Hockley is co-founder and managing director of Sandy Hook Promise, a national nonprofit dedicated to preventing shootings, violence, and other harmful acts in schools through evidence-based “Know the Signs” programs and bi-partisan state and federal policy.