But Twagirayezu remained troubled by his past. Gakuba remembers nights when he was awakened by Twagirayezu screaming during nightmares.
"He is trying to put that behind him," Gakuba said. "He kept it buried inside of him. It's not something you can get over. I just feel very fortunate that he doesn't have mental problems because of what he witnessed."
At Owings Mills High, Twagirayezu ran track, played on the soccer team and was selected for the Honor Society. During his senior year, Twagirayezu's uncle felt it was time to revisit the past and took his nephew back to Rwanda to see his relatives and his childhood home.
"It was tough going back," Twagirayezu said. "It was difficult to see those places again."
Twagirayezu transferred to the University of Maryland after spending one year at Drexel University in Philadelphia. He studies civil engineering and works such campus jobs as driving the university shuttle.
"When I look back, it's a miracle he survived," Gakuba said. "And it's a miracle he turned out the way he did."
This year, Twagirayezu has become involved in the effort to focus attention on the estimated 400,000 people who have died in the Sudan violence.
This spring, he told his story of survival at a Sudan rally on campus. An official at the national organization Africa Action also spoke and asked Twagirayezu to speak at the group's rally in front of the White House on the 11th anniversary of the Rwanda genocide.
Standing next to national figures, including actor Danny Glover and Rep. Donald M. Payne, a New Jersey Democrat, Twagirayezu told his story of loss to about 200 people.
"My skin had goose bumps," said Akenji Nduma, an Africa Action associate. "I was speechless, and everyone was speechless. When you know the gravity of 800,000 people dying, and he was so close to being one of those people, it's just amazing."