There's a fairly well-known study (I could find a ref if wasn't too lazy) showing that people in retirement homes who were made responsible for the care of a po

There's a fairly well-known study (I could find a ref if wasn't too lazy) showing that people in retirement homes who were made responsible for the care of a potted plant, lived longer on average than a control group who were given a potted plant but told the staff would take care of it. Just having a responsibility keeps people alive.