Siblings not pulling their weight

Had to get this off my chest. My DH is the only one of six siblings living in this country. He has elderly frail parents who are almost 90 and his mum is in and out of hospital. His dad is able to get about a bit but has his own health issues and is getting a bit confused. My gripe is the lack of interest, concern and sense of responsibility shown by his brothers and sisters. They rarely get in touch, a phone call from them being a big deal. They assume were exaggerating when we say how frail they are. One brother has not seen them in almost ten years, another two years. Others who could easily visit haven't made the effort for nearly a year. However, one of the most annoying things is, during their rare phone calls, they advise dad to do X Y and Z in direct opposition to what we've advised, eg they should take a holiday ( we would need to do the transportation), get rid of the man who does the garden ( we d need to do it till replacement found) get double glazing in ( they chose dodgy company and we had to sort out mess) remain in their too big house with stairs ( putting them off a perfect sheltered housing house which they were considering) It make me mad and causes DH a lot of stress especially as his folks are stubborn and difficult to deal with at best of times. Anyone else in same boat?