The day after the doctors' tests came back, Michelle Valentine rushed to church. She sank low in an empty pew, gripped its polished oak edge with both hands, and waited.

The mass began. The priest's first words startled the crowd: There was a woman here today, he said, 25 years old, single, the foster mother of an infant no one else wanted -- a baby girl now not likely to live past her second birthday.

Valentine wiped her face. Quit crying, she remembers thinking, you're giving yourself away. She sat in the middle of the church, next to the center aisle, alone and anxious. When would the priest ever reach his sermon? She believed it might offer a reassuring message, some cold rag of wisdom to fight the fever of her pain.

The priest completed the gospel reading, then stared at Valentine. He had clasped her hand on his way to the altar. "Unfortunately, God allows suffering." His voice rang with quiet force. "And we will suffer over some things. We might think our grief will never end. But remember: You suffer less, much less, when you are doing something good, even if, in the end, things turn out badly."

Valentine relaxed. At least she was doing good; she promised to remember that.

All around, there were parents with healthy children at their sides. She resisted envy, and appreciated the infant she had volunteered to keep: Christina. Born three months premature. Abandoned one day later. Addicted to cocaine. To heroin. Brain-damaged. And infected with amysterious virus, identified the day before as AIDS.

Michelle Valentine bought a case of baby formula last week. She's not sure if doing so was wise.

"Usually, I only buy a couple of cans," Valentine says now, more than three months after memorizing the priest's comforting words. "I'm always thinking, 'What if ...' It's taken me this many months to decide it's okay to buy extra formula. You just can never think about tomorrow. You want to plan ahead, but you just can't. It's like Christina is being robbed of time."

Christina -- the name Valentine uses in interviews to protect the privacy of her foster child -- is 8 months old. She weighs 11 pounds, scarcely more than a healthy newborn. The veins in her arms are so weak that doctors recently had to stick an intravenous feeding tube into her head. To do so, they shaved her thin brown hair. It is slowly growing back. Still, Christina does not look ill. Her skin is clear and creamy pale. Her tiny eyes are bright blue.

"I still don't believe there's been a day that's gone by without a tear coming down," Valentine says, resting on the couch inside her apartment. Toys clutter a playpen in the corner of the living room. For three hours, Valentine speaks softly; the conversation seems locked inside one long sigh. She hardly moves, but nervously twirls an index finger through her wavy brown hair. She lapses into solemn, lineup-photo stares born of frustration and disbelief.

"It's just so horrible knowing now that all Christina is doing now is fighting to die," Valentine says. "That's it. Before we knew that she officially had AIDS -- God, I had so much hope. But now it's so frustrating. We're just buying as much time as we can."

So foster mother and foster daughter enjoy each day exactly for what it is: another day. Each weekday morning, Valentine leaves Christina with a baby sitter before starting work in the accounting department of a real estate company. She eats lunch at home with Christina. A nurse visits twice a week.

Christina also receives a checkup about once a week at Washington Children's Hospital; she is examined especially for early signs of infection or neurological deterioration. (Medicaid covers medical costs; her local government pays nearly $500 each month for Christina's living expenses and special needs.)

Each night, Valentine playfully gives Christina speech lessons. "We're into the vowel sounds," she says. Crawling exercises follow: "She can't grasp the concept yet," Valentine says. "But that's because she's so spoiled -- I never want to put her down." Sometimes Valentine props Christina on her bed and talks, or takes a few more pictures. Always more pictures. On the night Christina first came home, Valentine shot two rolls of film, "snapping every little move."

That was in February. Christina was 8 weeks old and had never left her hospital's intensive care unit. At that time, though, she had tested positive for antibodies of HIV (human immunodeficiency virus, which causes AIDS); there was still a chance she could escape AIDS' grasp.

"The infants born to mothers infected with AIDS will have the antibodies at birth, but that doesn't necessarily mean they've actually got the virus," says Dr. Shelby Josephs, AIDS physician coordinator at Children's Hospital. "Only about 50 to 60 percent of those infants will actually be infected." The remainder lose the antibodies before they are 15 months old and become healthy children, he said.

Valentine knew the odds. And ignored them. It was so wonderful to have a child, especially one who needed this much attention. When she volunteered to become a foster parent, she figured any child would do. These days, she analyzes that decision in a weary tone that suggests everyone wants reasons more complicated than she has to give: "I had room in my apartment. And I had love to offer. I thought, 'Why not help?' "

She attended foster-parent training last fall. Since she was single and lived alone, Valentine knew that foster care officials would not likely place a child in her care. They prefer families. The best Valentine hoped for was short-term emergency care; she expected that if she ever got a child, it would be only for 30 days. Then she met someone who changed her mind.

This new friend, who would become Christina's godmother, will not allow her name to be printed. Her foster child, a boy she identifies only as a toddler, tests HIV-positive. He does not have AIDS -- yet. And since he could lead a normal life, she does not want anyone to know who he is.

The two women met at the training program. Valentine visited the friend's home, adored her foster son. In January, the friend heard about another baby with the virus who had been abandoned and who foster care officials could not place. It was Christina. (Neither Valentine nor foster care officials will say anything about Christina's natural mother.)

"Some people at social services asked me if I knew anyone who might want this child," the friend recalls. "So I called Michelle, explained the situation to her, how she would be at low risk -- but not at no risk -- of getting the disease. And she said, 'Fine.' Just like that. She was so excited she wanted to get the baby that night. I called social services back immediately, and said, 'Have I got a mother for you!' Everything moved very quickly. It became our cause ce'le`bre to liberate this baby from the hospital."

Valentine met Christina a few days later, a Monday night. She returned to the hospital on Tuesday and Wednesday, arriving from work, staying until midnight, and receiving a crash course in AIDS 101: If the baby's nose bleeds, wear disposable gloves. If the baby's blood spills, clean the spot with bleach. Anything Christina soils must be wrapped in plastic before disposal.

Then, on Thursday, Christina was ready to go to her new home. Valentine does not remember being frightened. She knows she was thrilled. "I rushed up there right after work," she says. The memory lights her face. "Of course, traffic was so bad. I thought I'd never get there. Then when I finally get there, they've got all this paperwork waiting for me to fill out. It was like: Fine. Fine. Fine." She pauses and laughs. "God only knows what I've signed."

About an hour later -- after the nurses finished crying and taking pictures -- Valentine drove Christina home. There was so much joy that night. All those pictures. Valentine called friends and let Christina cry into the phone.

She suspects now that she underestimated the consequences of her decision. She would need much more than grace to deal with these pressures: the confrontations with hysteria -- at work, in her family. Christina's baffling rashes that had Valentine calling friends and frantically flipping through the pages of her Dr. Spock book. The sudden high fevers. All the anxiety most new mothers fight -- except that every sniffle or sneeze might mean Christina would never return to the crib Valentine bought for her.

Once, she left Christina overnight in the hospital for tests and, returning the next morning, was shocked to find her zipped inside an oxygen tent. In May, Christina had a coughing and choking spell so long and painful her face turned blue. The rescue squad came that day. Valentine knew it was no false alarm. The next day tests proved Christina had AIDS.

"The few foster mothers who choose to take on this awesome burden -- to bring such sick babies into their lives -- live entirely on hope," says Dottie Ward-Whimmer, a Children's Hospital nurse who helps treat HIV-positive children and those with AIDS. "They look at that baby and say, 'Why can't this be the one who beats it? Somebody's got to.' These mothers appreciate these kids with exquisite intensity. But they live on a tightrope."

Suddenly, Valentine was watching that rope twang from the ground. "I was in hysterical tears all night," she remembers. "It was such a helpless feeling. I kept saying, 'I just don't want her to suffer, I just don't want her to suffer.' "

The next day she attended mass -- "searching to hear anything that would help me feel better." For the next month, she left work each day at 5 and visited Christina until midnight. The infant's odds had been substantially cut; statistics show that children with AIDS rarely live more than two years, Ward-Whimmer says.

"I hate this disease so much," Valentine says. She pauses. "You know, I was reading that Newsweek the other day, the one with all the AIDS victims' pictures in it. I couldn't stop crying. It's like a yearbook of dead people. All those pictures. And I kept imagining I'd see Christina in there. I know it's the future. It was right there on those pages. Right there -- in my face."

When Michelle Valentine walks though shopping malls, she lies.

It always happens: Someone notices Christina in her stroller, moves up close and donates praise. "I'm always having people come up to me say, 'Oh, what a beautiful baby you have,' " Valentine says, smiling. "And I always take all the credit."

If they only knew. "Oh God," she adds, rolling her eyes, "everything would be so different." Valentine suspects that were she to tell people the truth -- that she's The Foster Mother of the Baby With AIDS -- they would panic, like some of her former coworkers did a few weeks after she brought Christina home.

She brought meatballs to an office party at the bank where she used to work, Valentine says, "and the next day, the people who knew I had Christina and knew she had tested HIV-positive, told other people, and word spread. And, all of a sudden, we had a bunch of people in the office thinking they might get AIDS from my meatballs.

"My boss called me in and said, 'Michelle, I've got a hysterical group of people here vowing not to work until you open up to them.' It was a big mess. We had to call someone from social services and have him come down and explain just how little risk I was in."

Most tension disappeared. But not all. Valentine remembers one coworker who would not walk the hallway at the same time she did, another who would not grab gum from the same office candy jar. Outside the office, she still struggles to solve The Baby Sitter Problem. "It's been real tough for both of us at times," Valentine's friend says. Once the sitter hears about AIDS, "You get that 'have-a-nice-life' look, and they're gone."

But Valentine dismisses such problems. Her response to others' fears remains the same, she says: Yes, she's at risk, but it's a very small risk that can be eliminated with common sense -- wearing gloves, using bleach and so on ("the bottom line is blood ... that's it," she says). She tested negatively for HIV in April. But what's really more important, she contends, is to protect Christina from others, not them from her. The infant faces great risk of contracting a germ that leads to infection, deterioration and death.

Valentine says she has lost patience repeating that point. Few understand it -- especially her brother, 30 years old, married, the father of a 6-year-old boy. She has not seen him since February. That's when they last spoke. That's when Valentine and Christina were no longer welcome in his home. And that still hurts.

"When he told me that, I think I was in a state of shock," she says. "I was like, 'You're kidding, right?' But he said, 'I just can't take the chance.' I sent him all the AIDS information pamphlets I could find. I gave him doctors' phone numbers, called him every night for a week. But nothing changed. He'll never change his mind, unless there's an absolute 100 percent guarantee. It's not me. I know that. It's just Christina -- he doesn't want her in his house. And I don't want to be welcome there alone."

She pauses and leans back on the couch. The next words emerge slowly, and her voice trembles. "See, I think his fear isn't just for his family. I think he really fears for me, too. I think he believes I'm really going to die, that what I'm doing is just so dangerous, just so stupid ..."

She frowns. Life goes on. Valentine says she has not once regretted choosing to care for Christina. "It's extremely clear that Michelle adores children," Valentine's friend says. "What we are going through is emotionally draining, but when we look at the babies we have, how cute and lovable they are, we know the blessings far outweigh all the crap."

"You just can't keep those kids in bubbles," Valentine says. "I couldn't stand the thought of Christina abandoned and stuck in a hospital like she was. I guess I don't have the fears other people have. I thought, Why not?"

So, less than a week after the friend first told her about Christina, Valentine became a foster mother. Just like that. It's how a lot of things have happened. Eight years ago, Valentine's 42-year-old mother collapsed and died in the kitchen of their Northern Virginia home, a victim of heart disease. Valentine was right there. She was 17, and her mother was gone. Just like that.

Valentine was left to care for her 11-year-old sister; her father, a weapons inspector for the Marines, often was away on business. Her brother already had moved out. "It was a real good taste of mothering," she says.

One month after she graduated from high school, her father announced a move to California. Valentine did not want to leave her friends. She stayed, and her father and little sister left. Just like that.

Valentine moved into an apartment. She lived alone, studying criminal justice at Northern Virginia Community College at night ("I wanted to be a police officer," she says), operating a day-care service at home during the day.

She speaks regularly to her father and sister. They have seen all those pictures of Christina. And they support Valentine's decision. "At first, they asked why, just like everyone else did. Everyone still keeps asking me, 'Why?' or 'How can you do this?' " she says.

"You know what my question is to everyone who asks me why I'm doing this?" she asks. "My question to them is why aren't they interested in doing this kind of thing. AIDS is not my problem. This horrible disease is everyone's problem."

On that point, foster care officials agree. They expect more infants to be born infected with HIV, and more to be abandoned. "The problem is just starting here," says George Baker, chief of foster care and continuing service in the District. He says plans are being made specifically to recruit foster parents for HIV-infected children. Lynne Fountain, supervisor of foster care home-finding for Alexandria's social services department, says an AIDS workshop was held this spring to fight the fears of potential foster parents, and another has been planned for the fall.

"There's so much resistance," Baker says. "You can give out all the facts and you will hear people say, 'Yeah, I believe you, but I still don't want to take a chance.' "

Baker estimates that about four HIV-infected children have had to be placed in foster homes in the District. Foster care officials in Alexandria and Arlington and Fairfax counties say they have had to find foster care for HIV-infected children once or twice. Officials in Montgomery and Prince George's counties say they have yet to place an HIV-infected infant into foster care.

Most infected infants have been able to remain with their families, officials say, but that is often a struggle. "We have a terrible time finding family members to stand by the mothers who give birth to infected children," Ward-Whimmer says. "Those mothers -- they're often so physically and emotionally overwhelmed by what's happened -- have to deal with so much guilt. If they say, 'My child is HIV-infected,' they have to deal with, 'Well, you're the one who gave it to them.' Some just can't take that and give the child up."

Approximately 50 children who have tested HIV-positive are being treated and tracked by Washington Children's Hospital; only five receive foster care. But Dr. Josephs says he expects the problems to get worse, especially in light of the crisis New York City has with AIDS and foster care.

There are 75 HIV-infected or AIDS infants now receiving foster care in New York, said Ann Ormsby, deputy director of public affairs for the city's human resources administration. Another 25 HIV-infected children are stranded in hospitals -- medically fit to leave, but without anyone to keep them. The city recently began a program to recruit, train and counsel foster parents of HIV and AIDS infants. "It's only going to get worse," Ormsby said. "It's not impossible to find people to do it, but it is rare."

As officials craft strategies, Valentine works to give Christina company. "I would take another AIDS baby right now," she says. "I've already tried to get them to let me care for another one. I could handle it. Mothers have twins. I'm up at night anyway. I know I could handle another for a little while, but maybe not for a life commitment. I promised that commitment to Christina -- to see her through this. To the end."

Christina's awake.

It's as if she fell from a tree. Her eyes suddenly click open. Her feet thump the sofa cushion. Her cries chase silence from the dimly lit apartment. Valentine lifts Christina above her lap, patting her back, kissing her forehead -- soothing gestures that soon stop the tears. The conversation continues. The new topic is the future. There's not much to say.

But Valentine does have a few plans. In December, she hopes to begin investigating what needs to be done to gain complete custody of Christina. A foster mother has the right to make such a request when a child has been in her care for one year, Valentine says. She wants to get an early start.

Valentine gazes at Christina; she speaks in high-pitched whispers, as if no one else is there. Just mother and daughter, inches apart, talking: "That's what I'd love to do, become your official mom ..." Christina taps Valentine's nose with her tiny fingers. "I bet you'd like that, wouldn't you? ... That would be a wonderful gift for your birthday, wouldn't it? ... that's right, it sure would ... come December we'll go get it done ... come December ... come December ..."