"My son is not dangerous," Carol Race told The Associated Press. "The church's action is a certain community's fears of him. Fears of danger versus actual danger."
Autism is a complex developmental disability that strikes one in 150 children -- one in 94 boys -- usually before the age of 3, according to the Centers for Disease Control and Prevention. The disorder takes its greatest toll on a child's social interaction and communication skills.
The numbers of children with autism have dramatically increased in the last decade, but it is not clear if the disease has become more prevalent or if doctors are just getting better at diagnosing.
"Fortunately, we are seeing increased awareness and a greater willingness to understand autism," said Marguerite Colston, spokeswoman for the Autism Society of America, who has an autistic son the same age as Magi.
But with few support services outside the schools, "parents and communities have to figure things out for themselves," Colston told ABCNews.com.
The autism society recently published a booklet -- "Growing Up Together" -- to help children better understand the disorder. It describes "unusual" behaviors, such as difficulty talking or not talking at all, flapping hands, avoiding eye contact and trouble reading facial expressions.
The sound of a school bell may hurt their ears; some have trouble eating food because of taste and smell sensitivities. "On the other hand," according to the booklet, "things that bother most of us, like a bee sting, may not appear to be as painful to them."
Integration and modeling typical children is important, according to Colston. "When children with autism become more and more isolated, the stranger they will be."
Like Magi, other children with autism are much more likely to show self-injury and property destruction than hurt others, according to Wayne Fisher, director for the Center for Autism Spectrum Disorders at the University of Nebraska Medical Center.
"We don't see a lot of danger when they integrate," he told ABCNews.com. "These are unusual cases."
"They are likely to display strong emotional reactions to new situations and changes in environment," Fisher said.
Magi might well have adapted to her new Girl Scout troop after several more visits, as routine is important, he said.
"But their behaviors are not well understood by the general public and it makes them uncomfortable."
And research shows that typical children also benefit from interacting with autistic children, showing improvements in patience, social skills and communication.
Michael Alessandri, executive director of University of Miami's Center for Autism and Related Disorders, called the Klages' incident "shocking."
"Children with autism are often excluded because of lack of understanding of their needs and because their special needs have not been appropriately accommodated," he said. "We hear of this far too often."
In May, a mother in Port St. Lucie, Fla., considered legal action after her son's kindergarten teacher led his classmates to vote him out of class. Alex Barton, 5, was being evaluated for autism.