Adrianne Woods strokes her son's forehead. The boy's long lashes drift closed, then flutter open as he shudders with a seizure.
"He's tired," Woods says of Xavier, who is almost 6 years old. "He's had a long day at school."
Nearby, Xavier's baby sister, Quinn, plays with their father, Anthony Byrd, on the floor of the family's Linthicum home. She rolls over, grabs at candy-colored rings and giggles.
Xavier has never rolled over, or crawled, or walked. He will never run into his parents' arms or call their names. He cannot see. That he smiles at his parents' voices and attends kindergarten is something of a miracle, his parents say.
Xavier has Schinzel-Giedion syndrome, an extremely rare disorder caused by a genetic mutation. The chances of being born with it are less than one in a million, according to Xavier's genetic counselor. The average life expectancy is two years.
"To us, he's just our son. It goes beyond special needs. It goes beyond this extremely rare disease," says Woods. "Every day with him is a gift."
"He's made us do things we never thought we could do," adds her husband.
While Xavier's condition is extremely rare, having a rare disease is not. Advocates have created Rare Disease Day, marked on the last day of February, to draw attention to these conditions.
By definition, a rare disease affects fewer than one in 200,000 people. There are more than 7,000 recognized rare diseases. Some are widely known, such as muscular dystrophy, cystic fibrosis and Huntington's disease. Others, such as Schinzel-Giedion, are the rarest of the rare.
One in 10 Americans will be diagnosed with a rare disease at some point in their lives, according to Global Genes, an organization that connects, educates and advocates for people with rare diseases.
Doctors struggle to diagnose conditions such as Schinzel-Giedion. There are no established treatments, no websites, no support groups. The diseases are complex and usually debilitating, affecting many different body systems.
"Physicians are taught to look for the common," says Nicole Boice, founder and CEO of Global Genes. "They hear hoofbeats and look for horses. But sometimes, you need to look for zebras."
Struggle to diagnose
Doctors and nurses fell silent when Xavier was born. His facial features were unusual and he was having problems breathing. He was whisked off to the neonatal intensive care unit; Byrd followed, bewildered.
There had been no clue that anything was unusual during the pregnancy. Routine ultrasounds did not catch any abnormalities.
In the days after Xavier's birth, doctors noticed more problems. MRIs showed he was having frequent seizures. Doctors decided he should be moved from Anne Arundel Medical Center, where he was born, to Johns Hopkins Hospital.
"We didn't know what was going on, and we had to put our faith in something," says Byrd, 40. "We decided that whatever the doctors said, that was what we were going to do."
Xavier remained in the NICU at Hopkins for a month. He learned to take a bottle, began to gain weight and was released, although he still did not have a diagnosis.
"He was free of wires and tubes," says Woods, 35. "He was ours."
Both parents praise their employers for allowing them to take leave and work flexible hours to deal with Xavier's medical problems. Byrd works in information technology; Woods works with a Hopkins lab unrelated to Xavier's care.
Doctors focused on managing Xavier's symptoms. They experimented with medications to control his seizures. He underwent several operations to correct other problems.
Meanwhile, Hopkins geneticist Dr. Julie Hoover-Fong was working to diagnose Xavier's condition.
A break came when a genetic counselor in her office came across a description of Schinzel-Giedion and recognized Xavier's symptoms. Hoover-Fong's office sent a sample of Xavier's DNA to the Dutch lab that found the gene responsible for the syndrome. Xavier was a match.
"Technology has advanced such that we have the ability to sequence all the genes people have," said Hoover-Fong. "The diagnostic odyssey is shortening."
While Schinzel-Giedion is a genetic disorder, it is not hereditary. Instead, it is caused by a random genetic mutation soon after conception.
It took two years to diagnose Xavier's condition. That's faster than most. It takes an average of five to seven years to diagnose most rare diseases, said Boice of Global Genes.
Disease without a name
Angela Sittler of Essex is still waiting for a diagnosis for her 11-year-old son, Jacob.
Jacob was born with a clubfoot, extra fingers, and problems with his bladder, stomach and heart. He began to walk independently in the past year, his mother said.
Jacob has the cognitive ability of a typical 5- or 6-year-old but is unable to speak, Sittler says. He loves the Orioles and the Ravens — especially the cheerleaders.
"He's a flirt," says Sittler. "He loves to be around people."
Sittler says it is frustrating not to be able to name Jacob's condition.
"You're constantly in a cloud of the unknown," says Sittler, 39. "It's very isolating."
Sittler's struggles led her to want to help other parents. She works as the parent resource coordinator for the state's Office for Genetics and People with Special Health Care Needs.
Jacob's doctors at Hopkins recently made a breakthrough in the boy's case, Sittler says. After mapping his entire genome, they found that Jacob shares a mutation with a Canadian boy. Sittler hopes to connect with his parents soon.
"We might have a new syndrome," she says. "We just don't know."
Six months after the diagnosis, Woods and Byrd each decided they were ready to find out about life expectancy. It was two years. Xavier had already surpassed it.
They marvel at Xavier's ability to beat the odds, but they are also realists.
"We know the inevitable. We know how it's going to end," says Byrd. "But that doesn't mean we're not going to live."
Xavier's spine is twisted by scoliosis, and he suffers from hip dysplasia. He is fed by a tube, although he eats small bites for pleasure. He has the cognitive level of an infant.
He also loves hanging out with his baby sister, sitting in a swing and feeling the breeze on his skin, his parents say. In warm weather, Byrd sits outside with the boy in the evening, greeting neighbors and listening to the birds.
It hasn't always been this easy to make peace with Xavier's condition — especially for Woods. She fell into a deep depression in the year following his birth. At the urging of her husband, she sought therapy and learned to come to grips with his diagnosis.
The family received a huge boost last year from the Chive Charities, the philanthropic arm of a humor website. The organization gave them a wheelchair-accessible van, a special chair and sessions of cranio-sacral therapy to ease Xavier's symptoms.
His parents are also grateful to his teachers and caretakers. He attended a day care in Catonsville for special-needs children for a few years. Now he attends kindergarten at the Maryland School for the Blind.
A school physical therapist, Lynn Borgmann, helps Xavier stand using a special device. He can push switches on his wheelchair to play a recording or move his chair. Kindergarten teacher Casey Garrety says Xavier likes to be stimulated by strong scents, textures and vibrations. Most of all, he likes being around other kids, she says.
Byrd and Woods have connected with the parents of other Schinzel-Giedion patients through Facebook, sharing details of their children's triumphs and struggles. They know of about 15 others around the world.
But mostly, they figure out how to care for Xavier day by day.
On a winter evening, the couple settles Quinn into her crib, then gets Xavier ready for bed. They pour cans of a liquid nutritional supplement into a bag that slowly empties into his feeding tube during the night. Diaper on, fuzzy yellow blanket tucked around his shoulders.
"Good night, buddy," says Byrd, bending to kiss his son on the forehead three times. He lowers the hospital bed and turns out the lights.
"He's a child, just like anyone else," says Woods. "You want to say he was able to experience life."