NEWTOWN, Connecticut (WABC) -- Ten years later, they've come so far and accomplished so much, yet parents Mark Barden and Nicole Hockley acknowledge they still have so far to go and so much to do.
"There is still bullying and depression and suicide, but what we've seen is an increase in school shootings and weapons on campuses...and that is something that we need to work against," said Hockley.
Hockley's son Dylan and Barden's son Daniel both died in the massacre at Sandy Hook Elementary School on Dec. 14, 2012.
They are two of the 20 children and six adults murdered in the worst crime in Connecticut history.
Since that time, the parents of those children have turned their grief and sorrow into action and legislation.
They formed nonprofit groups to protect children from gun violence.
Some ways include training more than 18 million kids and adults through violence prevention programs, by spearheading gun safety laws under three presidential administrations and by supporting and counseling the scarred children who witness the deaths of their classmates.
The work is difficult and the mission is challenging - but the need is constant.
"The news of these horrible atrocities unfolding in our country, it can be difficult to keep that resolve but it also underscores the importance of the work that we do," Barden said.
Regretfully, those horrible atrocities have continued.
Since the shooting at Sandy Hook a decade ago, the Gun Violence Archive has recorded 27 mass shootings at U.S. schools - 19 of those were at elementary schools and another eight were at colleges or universities.
Those disturbing numbers could be even higher if not for the effort of Newtown parents like Hockley, Barden and the work of the Sandy Hook Promise Foundation.
"Eleven credible planned school shooting plots that have not happened as a direct result of our program and kids using our programs," Hockley said.
The measure of their success does not end there.
"In addition to the bad things that we are preventing, we are creating this culture of good things, of students who are more connected and compassionate and aware of each other and understanding the importance and the responsibility of just being there, being connected," Barden said.
And hopefully it's a culture of good things that finally ends the senseless violence that takes the lives of innocent children.
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