Ten-year-old Cameron Castillo never liked toys. It was the first thing about his childhood that gave his mother, Marie, pause.

Instead of playing with Tonka trucks, he clung to ridged bottles of Vaseline Intensive Care lotion. Birthday presents went unopened and were donated to Goodwill. Then, just before his second birthday, he stopped looking his parents in the eye.

"He just slipped away," says Marie, 42.

When he made grunting noises instead of saying words, Marie and her husband,

Fred, thought ear infections from his infancy had caused a speech impediment in their youngest of three children. But after they took him to a speech pathologist and an ear institute, Cameron's condition was diagnosed as autism,

a developmental disorder characterized by communication difficulties and abnormal social interactions, a few days before his third birthday.

It was 1996, and most people, including the Castillo family, associated autism with Dustin Hoffman's character in "Rain Man." But nothing about that movie -- or any other -- could prepare them for life with an autistic child.

Cameron had raging tantrums 10 times a day. He'd take off his clothes, scream "like someone was killing him," each time, Marie recalls. He'd fall or cut himself without anyone knowing until they saw blood trickling down his face. "One minute to the next, we weren't sure what would happen or what would get thrown at us," she said. "It was very stressful for our whole family."

Fred, a general contractor who often works a lot from his home, does not usually speak unless he has something to say. Much of what he talks about revolves around finding a cure for his son. His 19-year-old daughter, Danielle,

is away at Cabrillo College in Santa Cruz -- but when she's home, she defends Cameron and her family from strangers' disapproving looks and rude comments. Most think Cameron is just a regular kid behaving badly in public.

The Castillos' middle child, Lexi, 12, is a tomboy who excels at track and has aspirations to become a neurosurgeon. She says her classmates love "Cammy, " as she calls him, and they frequently write impassioned speeches for their classes about autism.

A poem Lexi wrote, laminated and tacked on her bedroom wall, sums up a lot of how she feels about her brother. "People laugh at him every day, but Cameron will forgive them anyway," it reads. "Cameron, he's a very loving heart, but even though autism is keeping him one step away from every day, he's a sweetheart."

Marie, a Mary Higgins Clark fan who loves mysteries, is sometimes overwhelmed by her puzzling son. The stay-at-home mother says that although he didn't start to speak until five years ago -- his favorite expressions are "pogo stick" and "play basketball" -- now he's learning to spell his name. Although his progress has been slow, she says, it's still progress.

His parents have learned more about the disease and how to fight it by joining Cure Autism Now and educating themselves about their rights as the parents of a disabled child. They give $10,000 to the nonprofit each year and sport a blue CAN sticker on the window of their truck.

But no matter how involved they are, they are not sure what to believe about the causes of autism. Fred wonders whether autism is caused by environmental factors. There are so many theories to consider, but not enough answers.

"We would love to see the Centers for Disease Control, the National Institutes of Health and the government quit dismissing this autism epidemic," Fred says. "These kids are being kidnapped and leaving behind a shell. We can't keep putting Band-Aids on this. It's a national emergency."

CENTER OF ATTENTION

At their five-bedroom home in Redwood City, a large American flag billows in the slight breeze. Few signs of life are evident in this cozy community of beige homes, other than Cameron playing basketball with his therapist. Inside the home, a slick baby grand piano sits in the corner of their living room and a soon-to-be discarded aquarium stands neglected by the front door.

Marie picks up Cameron's fleece and backpack, which he left at the bottom of the staircase. She makes it seem so easy to live a normal life -- but there are things that get to her. Neighbors and strangers see a normal-looking child whose parents let him run wild. When he plays basketball outside the house, drivers complain.

Marie shrugs it off. "They've told us, 'Kids shouldn't be out in the street. ' But we deal with people's reactions all the time."

The biases and slights are not personal, so the Castillos have learned to be patient. "Sometimes, people tell us that we should keep him indoors or not leave the house. We tell them, 'This is America.' "

It's a hot summer morning, and Marie races Cameron to the family's brown Tahoe truck after a tennis lesson and lightheartedly complains about being winded. Cameron, who is hardly ever tired, loves every bit of it.

The tennis lessons are Marie's break from her round-the-clock duties. If she had more free time, she says, she would take up golf. But there is no time to take a Saturday off with two children in the house.

She's up by 6:30 a.m., after having bathed Cameron at night and ushered him to the bathroom intermittently throughout the night so he doesn't wet the bed.

TWENTY THERAPISTS

During the academic year, Cameron attends school in Millbrae and splits his time between special-education and regular classes. By midafternoon, Cameron is in his therapy room with one of the 20 therapists he's had during the years.

The Castillos have tried dozens of treatments for him -- from low doses of Prozac to help with his concentration to vitamins and vaccinations. The costs have been as much as $13,000 annually, not including medical bills. MediCal and insurance foot some of the costs, but not all.

What has worked best for Cameron is applied behavioral analysis therapy, a method also known as Lovaas, which structures the environment for autistic children and rewards them for improving. The major challenge seems to be getting him to sit still for more than a few minutes at a time.

In his blue room, CDs of SAMONAS -- a sound therapy for children with speech and language problems -- are stacked atop the bookcase. Beyond a knotted blue spandex swing hanging in the middle of the room is a small table where a thick binder of worksheets lies among puzzles.

On a recent day, when his therapist came to the house, they stayed in the room for about 20 minutes before Cameron needed a break. She took him outside to shoot hoops instead of struggling with the worksheets.

When Marie is home alone with Cameron, she has a hard time getting him to simply sit down and watch a tape of "Goofy's Extreme Sports."

"He never just sits down and watches the movie, but I have to do something to get the laundry done," Marie says. "He'll be running around the house . . . unless it's his favorite part."

On a recent afternoon in Foster City, the family is having coffee with a friend, soaking in the bright sun outside of Starbucks. Cameron is playing with an empty coffee cup and saying "pogo stick" with a bright smile.

His progress gives the family reason to smile with him. But they worry about his future.

"Our biggest fear is that he'll grow to be 40 and we can't pass him onto his sisters and we won't institutionalize him. . . ." Her voice trails off. "He doesn't like to be alone for very long. When he is, he's like a toddler. He loves the smell of Windex, and if he isn't stopped, he'll eat soap."

When Cameron's condition was diagnosed, doctors gave Marie and Fred a list of things he'd never be able to do -- like drive a car or get married. As they have watched his development ebb and flow, the Castillos have kept their hopes for his eventual independence closer to their hearts than the threat of his slipping further away. Faith in the possibilities for his future is really all they have.