Let us give a little thought to this theory for just a second. (I'm not excusing anything just sayin'.) What if AB didn't have parenting skills or instincts. He and EB were very young when they had ZB. IMO neither of them knew exactly what to do. EB knew enough that she felt ZB would do better with AB. Maybe feeling his mum would help him. (Which she did.) EB felt she was still going to be part of ZB's life. AB or KB felt as though she abandoned both AB and ZB. (All speculation.) Now a young single father not knowing what to do at all, seeks help from his mum. She willingly and lovingly helps. AB's entire family does. The day to day care goes over to KB and DH. Responsibility is taken away from AB. He is now free to be ZB's playmate as it will. He has a daughter and he doesn't have to worry about her daily routine, knowing if she is sick or not, etc. He can play games with her, talk with her, without worrying if he is doing things right, or told he is doing things wrong. Now EB suddenly comes into the picture. She is forceful and loud. She begins to make decisions for AB if for nothing else to spite KB's authority. She takes over everything that has to do with ZB. Now she has a whole town looking down on her and judging her. So she decides they need to go to the States. They need to do things her way. Now they are in NC, AB is even more of a lost puppy. He is completely reliant on EB. He thinks she is a mum, she has raised her kids, she knows what she is doing more than he. If he questions anything, I'm sure she was quick to put a stop to it. (Such as banning people from visiting and talking.) I'm also thinking in the latter days of ZB's life, EB had began alienating AB from her too. I think the less people that were around to keep EB under control, the more conniving she became. I think AB's lack of responsibility skills allowed her to manipulate situations more easily too. JMO and one of many theories.