What age was he when adopted? It sounds as though he has aleays felt the odd one out, being the only boy as well. I wonder if he has tried to trace his birth parents. He may not have come to terms with being adopted which is sad. However, if he could not accept that your father simply could not afford the money, and that caused him to walk away, and more importantly, stay away after all this time, I would be very careful about opening the relationship up again unless you know what his character is like now. If he were to come back, would he, seeing that your father is elderly, hope for something to be left to him in his will. Do you know if this is the case? If not, it might cause another lot of trouble in the future. Obviously your sisters and father were hurt and do not want to be hurt again. I can only imagine how your father felt. Really we cannot judge - would it make your father happy to see him again before he dies, or would he get upset? You appear to have contact details for your brother, is there any chance that you could meet him for a coffee and gradually build up your relationship again - just the two of you initially, and letting him know that it is just you who is making overtures rather than the family. Once you get to know him a bit you could take it from there.