Sorry for the long back story, but I don't want to drip feed.
My DH's grandma more or less raised him, so we are very close to her. DH's grandpa died in 2009 of leukaemia, and grandma took care of him until the end at home. When he passed, she got friendly with a wonderful older gentleman who had also lost his wife, and their relationship grew to be more than friends. Grandma is in her mid 80's and her DP is in his mid 90's.
Earlier this year, grandma's DP was diagnosed with a form of bone cancer, which he had surgery and treatment for, that was supposed to set him on the path for complete recovery. Turns out the surgery did more harm than good, and he is now in a very bad way, unable to swallow, being fed through a tube, barely mobile etc.
They have never lived together, but spend alternate weekends at each other's houses. Ever since grandma's DP came out of the hospital, she has been looking after him as best she can, travelling the 25 miles between houses. When he is at her house, she takes on the responsibility of his medical care, and when he is at home, he has a community nurse go round a few times a day to sort out his feeding tube and medication. Now that might not sound like a bad situation, but the plot thickens.
His daughter lives 5 minutes down the road from him, she works part time, isn't married and has no children, but she doesn't seem to think visiting her sick father is important, let alone taking on some of the care responsibilities. DH and I live over an hour away from both grandma and her DP, and visit a few times a week, help with small things like shopping, and I do grandma's hair for her once a week, and DH sits and helps her DP catalogue his stamp and coin collections. Small things, but they make the both of them so happy. My DH's grandma is elderly, not in the best of health herself, and has already watched one man she loves die. AIBU to think that grandma's dp's daughter should be pulling her head from her backside and spending what little time her dad has left with him?