Ross and Cheryl,
I am so sorry for your loss. We also have a son with problems, he has aspergers syndrome, and due to medication has serious ups and downs, i don't think the medical profession has all the answers. As parents you can only do so much to help your children, and i'm sure you and Cheryl have done all that was possiable.
Our thoughts and prayers are with you, and we offer our deepest condolences.
Graeme and Lynnette