Thank you for the question Emma.

At the heart of all humans is an endless capacity to heal. Our beings are built for change and transformation. And this is especially true for children. But one cannot heal inside of the environment where the trauma is occurring. One can only survive. So, first, we have to change the environment. I use the term alignment a lot. Finding the right alignment for a person to thrive. And I show people a very simple tool for doing that, it's called Delicious Yes. It's a little challenging to practice at first, but it makes it really clear how to find alignment. ( THere is a free 9-day practice course on this at kirantrace.com/challenge.)
So,
Step 1 is to put some alignment back in place.
Step 2 is to witness how this child is finding connection. Maybe in himself? Or in plants? animals? etc.
Step 3 is to support the parents on how to witness this child making connections. ( Vs forcing it to be with them.)

Those are the beginning processes I would start with.

Much love,
Kiran