When Glinda McKoy arrived in the emergency room on the evening of Jan. 9, she asked a question she feared she knew the answer to: "Is my son dead?" When no one would tell her, when she was asked to wait while a doctor was summoned, she knew the answer was yes.

"That right there told me that my son was gone," she remembered.

Maurice Lashaun McKoy, 22, had been shot once in the head while he sat in the Woodbridge townhouse where he was living. And in the solemn ritual that unfolds whenever a brain is dead but a heart keeps beating, it was the hospital's turn to ask a question: Was Maurice an organ donor?

Yes, McKoy said.

Then she added one other thing: She had been waiting five years for a kidney to replace her own failing organs.

Knowing that her dead son could provide a near-perfect match for his grieving mother, the McKoy family and the transplant team at Inova Fairfax Hospital confronted the prospect of something experts say is phenomenally rare: using the organ of a dead child to aid a chronically ill parent.

McKoy hesitated at first. As inconvenient as her life had become -- four hours of dialysis every other day -- she was coping. At 49, she thought there were younger people who might need a kidney more than she did.

Then Maurice's fiancee, Jasmine Johnson, spoke up. Maurice had told her that if anything happened to him, he wanted his mother to have one of his kidneys.

"He made my decision for me," McKoy said. "There had to be a reason why all these things happened the way they did."

Maurice was kept on life support, and the next day, two procedures started on the hospital's ground floor: one to remove and prepare Maurice's kidney for transplant, the other to get McKoy ready to receive it.

Federal law allows what is called "directed donation," in which an organ donor or the donor's family can name a specific person to receive the "anatomical gift." Directed donation is unusual, said Sara Idler of the Washington Regional Transplant Consortium. Even more unusual is a patient receiving a vital organ from a deceased child.

"In the last 40 years, you'll probably not find more than 10 or 20 cases of it," said James B. Piper, the surgeon who performed the transplant. "It is a very rare set of circumstances."

Idler could recall only one recent case: Last year a Chicago mother received her 3-year-old daughter's kidneys after the toddler was killed by a falling tree branch.

According to the transplant consortium, more than 2,200 people in the Washington area are awaiting transplants. By far the longest waiting list -- about 1,650 people -- is for kidneys. The average waiting time for a kidney in the Washington area is four to seven years, Idler said. When McKoy received her son's kidney early Jan. 11, she had been on the waiting list for five years and on dialysis for nearly 10 years, her kidneys ravaged by high blood pressure.

Maurice McKoy was young and strong, a former running back on Gar-Field High School's varsity football team and a mover with Pullen Moving Co. That made his organs especially valuable. Idler said Maurice donated all his major organs -- heart, liver, pancreas, both lungs and both kidneys -- prolonging the lives of seven people, including his mother.

Both Maurice and his brother, Lee, had offered her a kidney, Glinda McKoy said. But she refused to accept, concerned that they might have medical problems later in life with a single kidney. "We're a family of diabetes and hypertension," she said. "I wanted them to have as much of a life as they could."

McKoy, who lives in Lorton, was registered for a possible organ transplant at the hospital where Maurice was taken, so the kidney "went from one operating room to the other," said Piper, the surgeon. As the kidney was stitched into her, it "started working immediately," he said. "You couldn't have asked for any better operation."

The successful transplant of a desperately needed organ is usually a time for celebration. In this case, though, Piper gathered the operating room crew and the nurses who would care for McKoy during her recovery and had a long discussion with them about what had just happened.

"I thought it was very important that all the people who were caring for her understood the circumstances," he said. "Everyone had to understand what she lost in order to obtain this wonderful gift."

After the operation, McKoy noticed the difference in her health immediately. With a functioning kidney filtering waste from her blood, her energy soared. She felt better, she looked better. And she could finally do something most people take for granted: She could go to the bathroom.

She was out of the hospital in four days, and yesterday she held Maurice's funeral in Alexandria.

No arrest has been made in his slaying, according to Prince William County police, who said the shooting appeared to have erupted from a feud between neighbors arising out of an alleged robbery.

McKoy said she doesn't know what happened on the Thursday night when a bullet flew through a window, taking her son's life.

"I just try to leave it all up to God," she said. "God has his reasons why things happen. I try not to get angry. Sometimes I do find myself getting angry, but I try to put it to better things." Those include assembling a scrapbook on Maurice's life, so that his 2-year-old son, Devon, will know what his father was like.

And she thinks about Maurice. "I know he is with me, not just by my having his kidney. . . . So many things remind me of him," she said. "Sometimes I feel sad, and just as soon as I feel sad, I feel happy again. . . . When I touch my stomach, I feel that he's really close to me."

Glinda McKoy, with grandson Devon, soon felt the benefit of her transplant.