Hi,
I'm so sorry to hear this. It can be a huge burden to bear. I worked for several years providing therapy services to children with autism in their homes. I'm sure the doctor will send you down the right road to getting these types of free services but if not, call the H.O.P.E. group or Guthrie Mainstream and they can start you on the path to getting someone to help out.
It's hard to explain autism because it's what they call a spectrum disorder. There's such a range of levels and types of symptoms. One kid's autism may just show up a little...maybe they don't make eye contact and they only want to talk about their favorite video game, while another kid may never learn to speak. The common threads are usually a lack of social skill and trouble communicating. One little girl I worked with had severe autism (she didn't speak and could be very agressive if you got in her space), and teaching her some simple sign language was extremely helpful. We taught her signs for her favorite things like her books and crackers, candy, and cheese. This cut down on her agressive behaviors because someone finally understood what she wanted, and it kind of helped her bond with those who would take the time to learn to understand her. It's also very helpful not to overstimulate these kiddos because they see the world so different, it's almost like the volume is turned up on everything for them. While you can't keep them in a dim lit room with classical music playing all the time, it helps to anticipate that they'll have a hard time if you take them somewhere like Las Vegas or the State fair, so you need to be emotionally prepared for that.
I hope I was even a little bit helpful. I know this was a long respose but it's such a complicated question. You're a wonderful great-grandmother to take the time to really try to understand what your grandsom is going through.
