I was diagnosed with autism in my late teens.
Autism is a very serious disorder that effects the human body.
I have a mild form of it. It mostly affects my social presence.
Sorry to hear.  Glad you are able to cope with it.  Did your parents notice in the first 2 to 3 years of your life?
Yes but it wasn't very common that long ago so I wasn't diagnosed till later in life.
My cousin has Autism.  
Do they have a severe case?
I would say not the most serve. It was gradual signs.  I would say it was a surprise as his development slowed it became known.
Probably more of a social thing.
Although Autism has some genetic factors no one on that side of the family has it. Environment does play a factor too.