johanna - marvellous of you to find out so much! I will certainly follow up on the ECHR - if someone out there has taken the trouble to ensure it is included, then there is hope. As for the therapist forum - we, until very recently, didn't know where they were - we have sent packages, letters, messages to our son's last work address; a parcel via a work colleague [who then wanted not to be involved] and nothing ever gets acknowledged. You might, others might, say give up, he obviously doesn't want to know, you must have done something really bad. I promise we have only done good things and the problem lies with the personality of our DiL. We were a small, loving and supportive family who never in our wildest nightmares saw this coming - if I could believe differently, it would make life easier. We did apply to family arbitration/conciliation, but unless they agree, it goes no further. We are convinced that the babies are being used as a weapon between they two - do this or else; who would not sacrifice a parent or two to that. But all guesswork. If only there was a 'legality' [not the right word I know] that gave us rights to access, the weaponry could not exist. The situation would have a basis for improvement.
Sorry, waffled on. And all to say thank you.