I have exactly the same problem as you. we were cut off from our grandchildren, their minds poisoned against us. Totally excluded without any reason or explanation, invited to Christmas lunch and then 2 days before received a message 'we don't want you in our house after all'! When our other sons tried to ask them what the problem was, they were told very upsetting lies. I was heartbroken at the time but have now learned to live without them and hope that the grandchildren will come back to us when they are old enough to see the truth. they no longer have contact with our other sons either. It has now been established that he has a personality disorder and we understand that he is seeking treatment. we have a split family. We never give up hope that he, DIL and GChildren will one day come back to us. I do so understand, Floriatosca.