After celebrating his wife's birthday Monday night, Quantaine Malone headed out for another long drive as a professional trucker. His 8-year-old boy walked him to the door, said goodbye and wished him a safe trip.

That was the last time Malone saw his son. The boy, Cameron McIlwain, was killed Wednesday night while driving with his mother and little sister on I-20 near downtown Atlanta. Transmission parts from a passing truck flew over the median and crashed through the windshield of their Chevrolet Blazer, slicing his mother's arm and striking Cameron near his collarbone, severing an artery.

Cameron's sister, 19-month-old Kanary, suffered minor cuts from flying glass.

When Quantaine Malone got the news, he drove 14 hours straight back from Iowa City with no sleep or food. He arrived Thursday morning at Grady Memorial Hospital as his wife, Jameka, was in surgery. Doctors amputated much of her right arm below the elbow.

When he was finally able to see her, Malone told her, "I'm here. I ain't going nowhere. I'm not leaving this hospital without you. I love you."

People in metro Atlanta know that highways can turn dangerous in a heartbeat, but Wednesday's tragedy was remarkable for how devastating it was, and how random.

The Georgia State Patrol released little information Thursday, simply saying that the incident, which occurred at about 7 p.m. Wednesday, remains under investigation. No charges have been brought against the driver of the truck, David Washington, who was working for CW Transport.

Malone couldn't help but wonder why the transmission came apart. Was the truck worked on prior to going out? Was it put back together correctly? Had it been properly inspected? All that went through his mind.

"I want to know how it happened," said Malone, 31.

Above all, though, the day revolved around comforting Jameka, 29. About 20 people gathered to lend support at the hospital — "church family and family family," in the words of one.

Malone said Jameka broke down as she recalled the wreck: seeing the truck pass and the flash of an oncoming object; the football-sized projectile rocketing through the windshield, hitting her and then striking Cameron in the back seat; pulling over and trying to stem the flow of blood from her arm; calling Cameron's name again and again, getting no reply.

"I'm sorry," she told her husband's brother, Gary Brown. She said she wanted to protect her children.

It's not your fault, Brown told her. It's just one of those random things that can happen on the road.

Jameka was headed to Brown's home in Mableton when the accident happened. She and Brown's wife get together every Wednesday for a "girl's night" unwinding over a glass of wine. Cameron was great friends with the Brown's boy.

Jameka's mother was also at Grady Thursday. She had been talking to her daughter on the cell when the flying debris struck. She heard her daughter say, "Oh," and then nothing. She called back again and again, but never got through.

Alysa Kelker also stopped by to visit. Kelker, 30, a nurse, was traveling behind Jameka when she saw the debris fly off the truck. When traffic stopped she rushed over and found Jameka bleeding. She made a towel into a tourniquet.

"Check my kids in the back seat," Jameka told her.

Kelker saw a man examining Cameron. He couldn't find a pulse.

At the hospital, Jameka recognized Kelker. "Thank you so much," she said

She introduced Kelker to her husband. "This is the woman who prayed with me," Jameka told him.

Those gathered at Grady were full of stories about Cameron, about his maturity, which was way beyond that of a kid going into third grade.

When his father was away for days on a trucking assignment, Cameron stepped up. He knew which days were the days for garbage collection. He knew how to calm his sister when she had a tantrum.

"I can't believe my son is gone," Malone said. "It's like a dream."