About 40 percent of those with autism disorder don't speak at all, and 25 to 30 percent have a few words in their vocabulary at 18 months but lose them later. (thebabycorner.com)
The idea that there is a spectrum of autism disorders highlights that children may have symptoms that range from being very severe with impacts in most areas of their lives, to more moderate symptoms that are less limiting. (kidsmatter.edu.au)