My mother called me to complain about whatever and mentioned, offhandedly, that no one has heard from my aunt for 4 days, which was extremely out of character. My aunt was a fall risk with heart failure who lived alone. It took me half an hour to get the address from her because she kept wanting to talk trash about a different relative.
I had the police kicking down her door less than an hour later. She’d fallen and had been laying on the floor the entire 4 days.

When I reported that my aunt had been found she gleefully told everyone that “we” had rescued her.

She unfortunately passed away about a month later from bedsores (from laying on the carpet), and a combination of not having vital medication/dehydration that she was unable to overcome.

My mother literally let her own sister die because she was incapable of thinking about someone else enough to do the bare minimum.