Maddyone what wise words you speak! As a fairly new GNetter I did not know Nanban until now. This story has made me cry. I am so very sorry. Sometimes people have personality disorders, this may be the situation here, I would not know of course. As a retired psychologist my alarm bells rang when I read the little chap had suffered broken bones but you would have spoken differently if this came from something which could be a threat to him still. I have met many GParents who are refused contact with their GC. It happens more than one might think and is one of the most agonising situations in society and far more common in the western world or in the more wealthy nations. Your psychologist of course spoke true, you can do nothing. But I hope you have ways for comforting each other. I am glad you are together, many of us have lost our partners. Remember your GC will one day be old enough to make their own decisions and legally able to see whomever they wish. Even if you fear they will not be given to them, you could keep sending birthday cards and little letters from your holidays etc. Some people buy two of these and keep one, in case one day they may be able to show the child that they always thought of them. I hope and pray that this very sad and distressing situation will pass, soon. Since this has happened twice - if I understand correctly - it might be a revolving stage and you may be invited back one day. My feelings on this are a little extreme so forgive me, but should a happy time come one day and you can see your family, GC included, again, I would take the precaution of wearing a secret camera. On no account reveal that you are doing this. It is to protect you in the unlikely case that something unpleasant should be blamed on you. I may sound paranoid, but the small vignette you have given does make me feel there are hidden agendas in their house-holds and to have such selfish, extreme reactions; you never know what such a person or people together might do.
With my very best wishes and love.