A sorry tale, Jeza.
Kind of self-fulfilling though. They never visit him, so he doesn't feel kindly disposed to them, so he doesn't bother to make out a will, so it ends up being a fight over who gets what. That is -precisely- why wills were invented.
I imagine that the people doing the shouting and fighting do not visit one another, either. They have been forced into close proximity by Ronnie's death and their existing rivalries are only magnified by having property to squabble over.
With regard to visiting, it's a no win situation. Regular visits to a particularly elderly relative can appear equally vulture-like, to the casual observer. So I dare say some people hold back to avoid this. The pattern of not visiting regulary can start when you get your own life established, after all. Especially if long distances are involved.