Kim Lucas was nervous her 10-year-old son would grow impatient waiting for his food or be uncomfortable with the new sounds and smells. When this happens, J.D. tends to scream or run back and forth.

Big sister Crystal was concerned about how other people would react.

"I don't like it when people stare at my brother," said 11-year-old Crystal. "I don't care about it for me, but he is my little brother. I don't want people making fun of him because he is autistic."

The mystery of autism, a lifelong brain disorder that affects communication and social interaction to varying degrees, changes family dynamics for parents and siblings.

Twenty years ago, two to five cases of autistic disorders were reported for every 10,000 people nationwide. Now researchers estimate the various disorders under the umbrella of autism affect as many as one in 500 people.

Florida's rise in reported cases follows the national trend. Less than 10 years ago, 984 Florida children were identified as autistic, according to state education department statistics. Last year, 6,190 were.

In the six-county Northeast Florida region, autism cases have risen from 101 in 1993 to 433 this school year.

Researchers acknowledge greater awareness and improved diagnoses have influenced autism numbers. But the cause of autism remains unknown. Early on, it was erroneously blamed on cold, uncaring mothers. Some researchers think non-specific environmental factors play a role in altering susceptible genes and are in the midst of a study to determine if that's so. Others have suggested, but never proven, a connection to toxins in soil, electromagnetic waves and chemicals in childhood vaccines.

There is no cure, but children who receive early treatment and intervention often show great improvement and can lead relatively normal lives.

J.D. has improved. While he still engages in the repetitive behaviors associated with autism, like running back and forth, he is more likely to sit still. He now eats at the table and puts his dirty dishes in the sink.

Some issues still need to be resolved. When J.D. gets upset or frustrated, he will pinch.

"It is like having a 10-year-old preschooler who can hurt you although he doesn't mean to," Lucas said.

"While there have been great times, it can be very aggravating and stressful," she said. "He wasn't potty trained until he turned 5 and he used to smear everything on the walls. But what are we to do? He is our son. We love him. That doesn't change."

But it does complicate parents' responsibilities.

Leyda Cooksey tries to find time to help and play with her three children, all of whom are under age 5, including a toddler with autism.

J.D. Lucas waits as his mother, Kim, helps him with his socks. She says J.D. is making great strides in socialization and self-sufficiency, such as putting on his own clothes. -- John Pemberton/Staff

JoAnn and Kenny Lynch have become experts in deciphering medical research and insurance forms as they make decisions regarding their son's schooling and treatment.

Parents struggle to accept that their child will likely never drive a car, marry or have children of their own. Instead they celebrate other accomplishments.

Siblings make do with less attention from their parents and try to balance their own lives with helping their families.

Kim Lucas quit her job so she can take J.D. from their home in Baker County to his private school in Duval County.

"He is learning and growing every day," she said. "Now he says hi to people. That wasn't something he did a year ago."

About half of all children diagnosed with autism remain mute or are unable to combine words into meaningful sentences.

Adapting to needs

The children are likely to engage in repetitive behavior like rocking back and forth or banging their heads. Some are sensitive to sound, touch, sight or smell. They often resist hugs and cuddling.

Parents search for possible treatments. They trade research the way some parents exchange recipes.

First they try to cope with the diagnosis.

When Cooksey learned that Kate, now 3, had autism, she spent days crying. At her mother's urging, Cooksey pulled herself together to help her daughter with the bright smile and soft, blonde ringlets.

"It was hard in the beginning because here was this 2-year-old crying and screaming for different things," said Cooksey, who lives in Clay County. "My immediate reaction was to give it to her, but if I did it would never provide an incentive to build her communication and language skills."

The family makes Kate ask for everything. Kate can't just point to the ball -- she has to say "ball" if she wants it.

Because of the developmental delay, Kate plays well with her 20-month-old brother, Jack. But Kate often wants to follow her big sister, 5-year-old Caroline.

When Caroline dressed up to pretend play as a princess, Kate put on similar clothes but she lacks the communication skills to play along.

"I do see the gap now," Cooksey said, "and I wonder what will happen when they all get older."

Parents of older children with autism say life becomes more complicated.

JoAnn and Kenny Lynch kept Shane at Sabal Palm Elementary in Jacksonville so he could interact with general education students.

In Northeast Florida, Duval County has the highest number of schoolchildren with autism at 323. Forty-four cases were reported in St. Johns and Clay counties, 11 in Nassau, 9 in Putnam and 2 in Baker.

While Shane should be entering middle school next year, his parents know their 10-year-old is behind his classmates developmentally and socially.

"Emotionally, he is more of a child," JoAnn Lynch said. "Kids in middle school are getting into sex and drugs and he is not equipped to handle that."

Tough on siblings

Beyond school decisions, parents must deal with issues at home. That includes deciding whether to have more children.

"When I first knew what was going on with Kate I said I didn't want any more children," Cooksey said. "If you have one child with autism, you immediately think you are more likely to have a second. Little did I know I was pregnant with Jack at the time."

Cooksey called Jack a godsend that reminded the family to focus on what they had, rather than what they lacked.

Until recently, someone would have to be outside with J.D. Lucas during his favorite pastime, walking the patio stones outside his house. Now, he stays close by, meaning less worry for his mother, Kim Lucas. -- John Pemberton/Staff

They monitor him for the warning signs they found in Kate. Although there is no concrete medical research showing that immunizations trigger the disorder, she decided against giving Jack certain shots.

While Kate takes up most of her time, Cooksey tries to balance all her children's needs. When Kate works with a therapist, Cooksey plays with Jack and Caroline.

Older children say they expect their parents to spend more time with their autistic siblings.

"My parents know I can take care of myself and that I'm OK so they don't spend as much time with me," Crystal said. "I mean it is expected, but there are times when I wish they would focus on me. But I have my friends and I know my parents love me."

Crystal is one of J.D.'s biggest advocates. Her voice rose with joy as she spoke of his accomplishments.

But her voice dropped as she wondered about the future.

She plans to take care of J.D. after her parents are gone. She even offered to stay home until she gets married to help out, but her parents have insisted that Crystal attend college and have a life of her own.

"I love my brother," Crystal said. "Sometimes he can be really difficult, but then I feel bad getting angry at him because he doesn't mean it."

For solace she escapes to the television in her room or goes out with friends.

Her elementary school friends come over; they're familiar with J.D. But she goes to the homes of her new middle school friends.

"It's just easier that's all," Crystal said. "They know not to say anything, but sometimes I just don't want to have to explain."

A little compassion

Adults don't always know how to respond to autistic children, either.

While the children will play together, their parents sometimes stand back unsure of how to react to Shane, said Kenny Lynch, a board member for the Autism Association of Northeast Florida.

"You don't want to fault people because they just don't know how he is and that they can be around him," Lynch said."People just don't know what autism is. But it still hurts."

As the public learns more about autism, Kenny and JoAnn Lynch hope people become more accepting.

Since Shane excels in reading and working on computers, they hope someone will one day hire him for a job with these skills.

"And I would like for him to be self-sufficient, for him to live on his own one day," JoAnn Lynch said. "I don't think that is too much for a mother to hope for."