It was the image of a little girl on the TV screen that first caught her eye--a gaunt, hairless youngster whose father was looking for his long-lost relatives in hopes that they could donate lifesaving bone marrow.

"Oh, the precious little girl," Virginia McGill said to family members as she sat in her Laurel home Monday.

Before the night was over, McGill would discover that the sick girl, 7-year-old Morgan Elise Hanson, was actually the granddaughter she never knew existed; that the child's father, Jon Hanson, of Lusby, was the son she lost track of decades ago; and that--although it's a long shot--she or some member of her family might be able to help save the little girl's life.

"I couldn't believe it," said McGill, 55. "I just broke down and started crying. . . . It's fantastic."

After hearing some key information about Hanson--that he was born at Prince George's Hospital on March 15, 1969, and that his given name was Johnnie Ray Peeples--McGill called the television station. She knew for sure that he was her son after she read more details about him in The Washington Post that day.

Hours later, about 9 p.m., he was standing on her doorstep.

"My mom grabbed me, and I gave her a big hug," said Hanson, 30. "It was tears of joy and relief. It was basically 30 years of weight lifted off our shoulders."

The elation caused by their reunion--mother and son had searched in vain for each other--was tempered by the occasion for their meeting: the need to find a donor for Morgan, who was diagnosed with leukemia in November and was released last night from Children's Hospital after weeks of grueling chemotherapy.

All of Morgan's immediate family members, often the most likely compatible donors, have been ruled out as acceptable. That means that doctors at Children's will turn to a national registry to find a compatible donor, a process that could take months.

Now they have another option: testing the compatibility of Hanson's mother, as well as his 35-year-old biological sister, who lives in Prince George's County, and her two children.

"They don't think it's likely," McGill said.

Indeed, Gregory Reaman, a cancer specialist at Children's Hospital, estimated the possibility as "probably in the area of one in 10,000 or one in 100,000."

But Hanson said he will take those odds; his greatest fear was losing his daughter and never knowing if his birth family could have helped.

For years, Hanson's main clue about his past came from a birth certificate he once saw. The rest of the information he had was somewhat murky. He said he knew that he was "in and out of foster care" for the first two years of his life; he also has memories of his mother, "being picked up by her on weekends."

It was that information, as reported in Monday's Post story, that tipped off McGill that Hanson might be her son. She said she continued to visit her son after he was placed with foster parents.

McGill said her son had been taken from her by the state after she went to social services to get help caring for him.

"I was a single mother working two jobs, and Johnnie had a medical problem where he would cry two days at a time. . . . I kept going through babysitters."

McGill's story is difficult to confirm because social service records are closed to the public. Nonetheless, she said that the foster parents and the state conspired to take away her son.

The child was adopted and his records were sealed, factors that later became a roadblock for McGill, who said she always longed to find her son. Her current husband--Hanson's father left her when her two children were very young--kept reassuring her: "When he gets old enough, he'll find you."

Hanson eventually was adopted. He went on to attend Northern High School in Calvert County. After a brief marriage and one child, he met his second wife, Jeanine, in 1991. On Dec. 22, 1992, she gave birth to the first of their three children, Morgan, who "loves horses and horseback riding," has a beagle named Lucky and is "uncommonly social," her mother said.

On Nov. 18, after Morgan kept feeling lethargic after an ear infection cleared up, she was diagnosed with acute myelogenous leukemia.

The treatment was intensive chemotherapy to essentially destroy normal bone marrow as well as the leukemia, then--with the cancer in remission--to transplant healthy bone marrow from a donor.

Because one's genetic makeup determines the compatibility of a prospective donor, relatives can be especially compatible. Parents are generally less compatible than siblings, and it's even less likely that grandparents could be good donors for their grandchildren.

Those odds didn't stop McGill from picking up the phone when she saw the TV broadcast.

McGill said that she doesn't normally watch the TV news but that her sister had turned on the set.

"That's Johnnie Ray," her sister cried out when he gave the date of his birth and other details on TV.

Hours later, her son confirmed the news himself. Earlier in the day, an investigator who read about Hanson's search had provided him with some key information that led to McGill.

By late yesterday, this much was clear: Morgan was home eating a Sloppy Joe; her dog, Lucky, was in the back yard; and she was expecting to meet her new grandmother soon.

"I am ecstatic to have Morgan home," her mother said, "and to be honest, that's the only thing that matters to me."