According to the Centers for Disease Control, about 1 in 88 children is diagnosed with some form of autism spectrum disorder.
The signs of autism are usually spotted in the first 3 years of life.
Dr. Thomas Frazier with Cleveland Clinic says, "By 24 months they should actually be putting words together and so we look for that as a very specific sign that kids are developing appropriately. Socially we want to look and see if they are engaging in a back and forth fashion. It doesn't even have to be verbal, it can just be using their body language, the way they look at the parent, the way that they are interacting."
The earliest you can really look for signs of autism is about 12 months old.
Kids developing normally should respond to their name, even if they simply look in the direction of the person who said it.
Small children should also be babbling or using single words when trying to make a request.
Any type of odd behavior should send up a red flag, such as flapping their hands or spinning in circles.
Early intervention is often an important part of treatment.