My brother (77) shoulders most of the day to day responsibilities at the behest of our mother (99). He is geographically closest to the care facility. My brother, myself, and my mother want my sister's adult children to step up and move their mother to a location near them but as yet, none have offered because, in my opinion, my sister is not easy or pleasant to care for. She's demanding, ungrateful, and takes no responsibility for getting herself well enough to be released. My brother wants out from under the burden, I'm not geographically close enough to be of much help, and of course my mother is too old. My sister's children are all adults and capable of taking over. How can we force the issue? Thanks.