I agree with your mother and with Victoria. In this day of super-specialization only your mother and her health care designate know the whole story and so can say what might not fit with previous decisions etc. Also, some say, that once you are over 80, doctors tend to do less not more for you - attributing most problems to accumulated age. Either way dealing with health issues is not for sissies.

It's easier to understand them if you take the time to learn about their world and the context surrounding their issues - then you become an informed listener - people notice and begin to trust you because they can tall that you took the time to prepare to listen.