Developmental disorders can comprise a lot of different type of disorders from language disorders to autism spectrum disorders. 
There is a lot of people out here with autism do you know many?
No but it can be hard to diagnose because it isn't usually show in the first two or three years of a childs life. 
I think there is a lot of research out there but I think it needs to be a lot more.
That's true but there is also some bad research out there like junk science that says vaccines cause autism. 
I'm sure there is some bad research out there but not really sure I trust the vaccines either.
They really as safe. All they do is provide immunity for a certain disease. 
I've also seen where someone has taken a vaccine and it made them walk backwards and not a requirement. I think it should be a choice.