These four events repeat every 'tropical' year (365 days, 5 hours, 49 minutes), so they become later by about six hours, or (if there has been an intervening leap day) earlier by about 18 hours, from one year to the next.
The three distinctive signs and symptoms of autism include problems with verbal and nonverbal communication, difficulties with social interaction, and repetitive behaviors or narrow, obsessive interests. There are three distinctive symptoms of autism.
List of Symptoms for High-Functioning Autism. Below is a list of common traits among children and teens with High-Functioning Autism and Asperger's. However, no child will exhibit all of these traits. Also, the degree (i.e., mild to severe) to which any particular trait is experienced will vary from child to child.