Floyd Reed McIntosh Jr. had spent almost two of his 21 years at Lorton Reformatory. Devoted to his mother and troubled by the brutal murder of his young aunt, he looked forward to his release this weekend and a long summer in the sun.

But Tuesday afternoon, with his freedom in sight, McIntosh's dreams were cut short. As he sat before a television set at the Occoquan I facility, McIntosh was fatally stabbed from behind, apparently by another inmate.

"They didn't have to do this to my baby," said a tearful Cynthia Crowder, as she rocked on a couch in the living room of her Southeast home in Randle Highlands, clutching a Mother's Day card from McIntosh and turning to members of her family for comfort. "Why is my son dead?"

Crowder received the news of her son's slaying while she was still trying to come to grips with the violent death in January of her younger sister, Janice Elaine Morton. D.C. police found the battered, nude body of the 20-year-old Morton in a Northeast alley. Morton had been sexually assaulted and strangled, police said.

Alton Alonso Best, a 31-year-old District resident, pleaded guilty this month to second-degree murder and sodomy in the slaying of Morton, whose death received widespread attention because of its similarities to the unsolved slayings of five women whose bodies were found in a wooded area in Suitland. He could be sentenced to 18 1/3 years in prison.

Morton's death hurt McIntosh deeply, his mother said. "He was very upset about his aunt," said Crowder. "Janice and Floyd were very close -- like sister and brother."

The slaying of her son, coming on the heels of her sister's death, has driven her to the edge of despair, Crowder said.

"The only way I'm holding on is my family and my faith in the Lord," she said, her voice shaking. "I'll never rest. I just want justice done."

McIntosh was fatally stabbed twice with a sharp, homemade object at about 4:30 p.m. Tuesday while he was watching television in the dormitory area of Occoquan I. His was the first slaying of an inmate by another inmate since the Occoquan facilities were built five years ago, D.C. Corrections Department officials said.

"I can't understand why my son was in that place and not guarded," Crowder said.

David Roach, acting administrator of Occoquan I and II, said he does not know if there were any corrections officers in the television room, but two corrections officers were stationed nearby.

Corrections officials said that McIntosh, who was serving time for car theft, had an argument with a 26-year-old inmate about 2:30 p.m. Two hours later the same inmate apparently stabbed him twice, in the neck and in the chest, they said. The inmate was transferred to Lorton's maximum-security facility the day after the stabbing.

Yesterday, McIntosh's girlfriend and family remembered "Floydie," as some of his friends called him.

"He was a wonderful son," said Crowder. "Anything you asked him to do, he did with a smile. He never gave me any back talk. He saw me through my crises."

"My brother didn't deserve to die," said Timothy Jerome McIntosh, 22, Floyd's brother.

Floyd McIntosh had been at Lorton since July 1985. Crowder said that her son was transferred from Lorton in November to Hope Village, a D.C. halfway house. McIntosh started drinking heavily the night he found out about Morton's death, and he got into an argument with a counselor at the halfway house, Crowder said.

McIntosh was charged with misconduct after that argument and transferred back to Lorton in February, she said.

But his family said all indications were that he was behaving and would be home any day. His girlfriend, Keesha Marshall, received a letter from him the day after his death.

"Tell everybody hello and I will see them in the summertime," McIntosh wrote.