What I would like to address in this paper is the difference between two forms of autism and an important development maturational process that leads to walking, crawling.
For my point of view at the beginning of life there is a symbiotic relationship between the baby and the mother and there is no difference between them. I agree with Fairbairn that the child is object sicking but this is from the adult point of view. From the child point of you the outside world, included the mother, is just dangerous and he displays all the possible aggression to protect from it, and if the adult is able to supply some stable and reliable condition, the child can start to disinvest the aggression from outside.
The autistic child looses the connection with the object and this state is exactly the opposite to the symbiotic stage at the beginning, the prognosis for this type of autism is not good especially with the progression of the age.
If an early intervention is applied in order to re-establish the symbiotic relationship that helps the child to trust again the outside world and then to disinvest the aggression from it and able to invest the object, then it is possible to restore completely the maturational process of the child.
I would like to use the analogy of walking to explain that, in normally development the crawling comes before the walking and a child that was able to crawl has more facility to walk.
At the end of the day walk and talking is a way to take some distance from the mother and able to have a distant relationship, that before was made by contact.
When the child arrives in therapy that is not playing and talking, what comes before is the play and after the child is able to put some words, sounds, songs to that play.
And what is the play? Re-establish the symbiotic relationship with the child, that can allow the child to crawl away and to talk and walk, when before he was running so far away lost in the dark space, falling for ever without landing anywhere on the ground, without the possibility to develop roots.
How you can see my interest is on the relationship and been able to be in it, and able to communicate these raw experiences to colleagues in order for them to experience it.