Raleigh, N.C. — Some children with Asperger's Syndrome, a milder form of autism, may go undiagnosed for years. The behaviors can be difficult for families, especially for siblings. One person decided to put his thoughts down on paper.

At 11 years of age, Sam Frender is like other boys his age, except he has written a book. It is about living with an older brother with Asperger's Syndrome. For 13 years, Sam's parents didn't know the cause of their oldest son's behavior issues.

"He was misdiagnosed at first as having anxiety disorder, then attention deficit disorder," said Robin Schiffmiller, Sam's mother.

The family then learned about Asperger's Syndrome and had him evaluated.

"(We) are so thrilled to finally know what it is," Robin said.

Sam's brother, who the family asked not to identify, fixates on a single interest.

"He only wants to watch Star Trek. He only wants to talk about Star Trek. He only wants to think about Star Trek," Sam said.

Sam, who said he feels protective of his brother, said it's hard to be patient. He also said he feels invaded when his brother wrecks his stuff. Sam and his mother knew his feelings were important, so they wrote them down.

"After we had so many on paper, someone suggested we publish it," Robin said.

Friends in Asperger's support groups have shared the book, "Brotherly Feelings," with their children.

"They thought it was pretty good, and that it really touched them," Sam said.