Pam Bosley is one of the grieving parents featured in Katie Couric's gun violence documentary Under the Gun

By Patrick Gomez
Updated May 25, 2016 05:20 PM
Credit: Sara Stathas

Pam Bosley fondly remembers singing along to gospel music while driving around with her son Terrell.

“He’d make fun of me, saying, ‘Mom, that’s not your key.’ I’d say, ‘Hey! I taught you how to sing,'” recalls the Chicago mother.

But after Terrell, 18, was shot and killed outside a local church while helping his friend carry drum equipment equipment into their choir practice in April 2006, her car stopped being a place of joy.

“I sat in my garage, turned the car on and tried to die from the fumes,” says the former banker, 51, who also tried to overdose on various medications in the months following her son’s death. “I was so angry with God but then I realized he was keeping me here for a reason.”

Now Bosley – who is one of the grieving parents featured in executive producer Katie Couric‘s gun violence documentary Under the Gun – has dedicated her life to making her neighborhood safer for her two living sons and to prevent any other parent from suffering a similar tragedy.

My husband and I did everything we could to keep Terrell safe, says Bosley, who still lives on Chicago s South Side with sons Terrez, 22, and Tre, 17, and husband Tom, 51, who works in finance. Bosley and her husband had encouraged Terrell when he took up the bass guitar at 15 and graduated from high school a year early with plans to pursue a music degree. But clearly that wasn’t enough.”

So Bosley and her husband founded the Terrell Bosley Anti-Violence Association and began attending anti-gun-violence rallies and marches. She also met with other grieving parents and in 2007 helped form the advocacy and support group Purpose Over Pain.

“We started sharing our stories with the media and advocating for commonsense gun reform,” says Bosley, who wants to see gun owners held accountable for the secondhand sale or loss of their firearms.

Five years ago, Bosley – whose son’s murder remains unsolved – quit her job to work full-time for the youth-outreach nonprofit the ARK of Saint Sabina.

For more on Bosley’s fight for justice – and how she’s learned to embrace music again as she sends her younger sons out into the world – pick up the latest issue of PEOPLE, on newsstands Friday

In addition to changing the laws, the youth are who Bosley says are the key to making lasting change.

“If we don’t change the hearts of the young people,” says Bosley, “then the cycle is just going to continue.”

Under the Gun premiered on Epix in May and will be available on Amazon and iTunes May 31.