Khalid is no stranger to stress. He dubbed his taxi the NYC Candy Cab after his 2-year-old son died in April from a long battle with heart disease.

“I learned a lot of things,” he said of the trauma of losing his child, who underwent two heart transplants and lost a kidney before he passed away. “Life is too short.”

Khalid, who moved to New York from Pakistan in 1993 and has been driving a cab since 1997, had already seen the impact of small acts of generosity. During the two years he spent in the hospital with his son, he routinely brought coffee and desserts to the doctors and nurses when he got off his shift at 1 a.m.