Family Dynamics

I discovered that all it takes is a family crisis to make an entire family fall apart.  My relationship with my sister has been suffering since November.  I apologized for a misunderstanding and then a week ago, my sister reemed at me for a half hour about the things I did which displeased her.  She came up to the nursing home yesterday and wanted to know if I had talked to my brother because he is blaming my sister for my mother being in hospice.  My mother's prognosis was determined because she failed the rehab tests.  My sister and I are on good terms for the time being.  However, now my brother and sister are having difficulties.