Bobby Tillman, the Georgia teenager who was randomly selected for a beating by teens outside a house party, attended a play at his church on bullying only hours before he was punched, hit and kicked to death.
The play at Lithia Springs Church of Christ, "Being Bullied," was produced by Tillman's grandmother.
"He had never been bullied until he was bullied when he passed away. When they killed him, that was bullying," his mother, Monique Rivarde, told ABC News.
The Douglas County Coroner's office confirmed to ABC News that Tillman, 18, died of blunt force trauma sustained during the attack. Tillman was battered and stomped so badly that one of his bones broke and pierced his heart.
Tillman's family will hold a viewing of his body this afternoon for friends and loved ones. His funeral will take place Saturday morning.
The slightly built Tillman only weighed 124 pounds. He was picked for the assault at random as he passed a group of teenagers who said they intended to attack the next male they saw.
"I knew Bobby was small. I always instilled in him that he's strong, he's a man, he has confidence and he didn't have to take anything from anyone -- there are ways to solve it," Rivarde said.
Four teenagers -- 18-year-old Emanuel Boykins, 19-year-old Horace Coleman, 18-year-old Quantez Mallory and 19-year-old Tracen Lamar Franklin -- were arraigned in Douglas County court Monday. Each was charged with murder and held without bond.
Coleman denied any involvement in Tillman's death. "I'm saying I'm innocent," he told ABC affiliate WSB-TV from jail.
"I don't think you'll ever know why it happened. It's senseless," Douglas County District Attorney David McDade said. "This is an absolutely unprovoked, senseless killing by young people killing another young man for no reason, no motive."
According to county police, Tillman was the innocent victim of a fight between two women and two men on the street outside a party Saturday. The argument escalated until one of the women hit one of the men, police said.
Instead of hitting the woman back, the man said he would hit the next male who came along, according to police. Tillman "came walking by and they beat him up and stomped and killed him," Douglas County Sheriff Phil Miller said.
Barbara Stephens, who lives across the street from the house where the party was held, told The Associated Press she saw Tillman fall to the ground and then saw one man viciously kick him repeatedly.
"I've been re-seeing it over and over," she said. "Every time I close my eyes I can see it. They were violent kicks. It was the worst thing I've ever seen."
Tillman was killed outside a house party that started out as a small gathering. According to police, the party got out of control after news of the event spread through e-mails and text messages.
Police who came to the scene loaded witnesses from the party onto a bus, a decision that caused some criticism from the local community.
"We brought 57 witnesses up here and that made some people mad," Miller said, but the sheriff insisted the move was necessary for the investigation.
Tillman graduated high school this past May and was preparing to attend college. His mother told ABC News he was a basketball fan.
"He just started training to become a referee, an official for junior varsity basketball for high school," Rivarde said.
He was too short -- 5-foot-7 -- to play basketball professionally, but he wanted to attend law school eventually and become a sports agent. "He said that if he couldn't be on the court he wanted to help the guys who were on the court," Rivarde told ABC News.
An "R.I.P. Bobby Tillman" page was set up on Facebook on Sunday where photos and videos have been uploaded.
In one entry a person writes, "out of 80 ppl at the party 1 person could have saved his life."
His family has now started the Bobby Tillman Memorial Fund through Bank of America to provide resources for bullied teenagers.