Spoke with my sister today. She's pretty clear that this is not survivable with any quality of life at this point. He has a Do Not Resuscitate order and they spoke with palliative care today. He has spinal abcesses but is too medically fragile for surgery; these are likely causing paralysis. He has pneumonia as well as infection in his sternum, 3 large strokes and more are probably forming, kidney failure and I imagine other organs are failing too.
She is strong and has the support of their three daughters (one each from previous marriages and one they adopted together.)
They've been married for about 22 years. My sister's first husband cheated on her and left her with a five year old child for an OW (and he's a sociopath but that's another story.). Her second husband's first wife had cheated on him. They didn't have a perfect marriage but he has been a generally good man and a good father, and faithful to my sister even during his occasional bouts with alcohol.