The number of American children with autism has jumped 78 percent in the last decade.
In the video above, see how parents have been frustrated by years of dealing with a condition for which there are still so few answers.
There are two major schools of thought on why the number of autism cases has exploded.
One says doctors have become better at recognizing it. The other says the definition of autism has broadened to include several conditions that weren't under that umbrella years ago. Aspergers, which Evan in the video has, is one of those conditions.
Some people believe both thoughts are correct.