ST. LOUIS – Windsor Park looks peaceful on any ordinary day. But 15 years ago, Darren Thomas, an aspiring chemist and father, was shot and killed there. Thomas was 36. His killer was never caught.

Gloria Shields-Snulligan, Darren’s mother, is speaking out to keep his story alive in the hope of finding some answers.

“He was one of the most loving, kindest persons,” she said. “He would help and teach anyone. Anything.”

Darren Thomas had built a home for his young son, a career, and a future his family believed was limitless.

"He was so intelligent that if I didn’t feel like thinking, I’d say, ‘Son, will you think for me?’ That’s how close we were,” Shields-Snulligan said.

But an argument one night in September 2010 resulted in Thomas’ death and sparked a mother’s quest for justice. Shields-Snulligan said she’ll never forget the moment she heard the news.

“I was in a shelter and my daughter came and told me. She said, ‘I think Derren got shot but I think he dead.’ And I didn’t get to pull the sheet over him, I didn’t get the opportunity to do it,” she said.

Fifteen years later, the case remains unsolved. Shields-Snulligan believes someone saw what happened that night, and is pleading for them to come forward after being unable to speak for close to a decade.

Now, she shares the words her son left her with and the faith she holds onto.

“My son would always say, ‘God will take care of them, mama. God will take care of them,” she said.