A new documentary features a father who lost his son on that day and the promise he made to him.
Musician Sheryl Crow is the executive producer of "A Father's Promise," which follows Mark Barden's journey from musician to activist -- and his efforts to use music to heal.
Barden is also the Co-Founder and CEO of the Sandy Hook Promise Action Fund, a nonprofit dedicated to preventing gun violence.
We spoke with the film's director, Rick Korn, ahead of its Friday night premiere at Look Cinemas in Manhattan.
for more features.