(NewsNation Now) — The father of a 7-year-old boy who was killed in the Sandy Hook Elementary School shooting in Newtown, Connecticut, said his heart is with the families of those lost in the Oxford High School shooting in Michigan.

Following the tragedy in Newtown, Mark Barden co-founded the Sandy Hook Promise Action Fund, an organization aimed at preventing shootings like the one that killed his son, Daniel, and 26 others.

Barden said the pain of losing a child never gets any easier.

“My heart and my thoughts are with those families right now,” he said “This is devastating and unreal. My heart is with them. What they’re dealing with, I’ve been living this for just about nine years now. And it never gets any easier.”

The Sandy Hook Promise Action Fund “focuses on policy and outreach efforts to advance sensible solutions that will prevent future tragedies and spare other families the pain of losing a child to gun violence,” according to its website.

Barden believes the key to stopping school shootings is to identify the warning signs.

“We know from research that almost always there are warning signs. And if folks are trained on how to identify those warning signs, and then they have the tools to get that individual connected to the help that they need or whatever services might help them through this,” he said.

Barden believes it’s crucial that children have an adult they’re comfortable telling if they see suspicious behavior at school.

“It could be a parent, faith leader, a coach, anybody in their network, who can then connect this individual to whatever supportive services they need, and get in front of this,” he said.