Whumpee who was infected with something, slowly dying and getting worse over a period of months, even years.
Caretaker who had to watch them get worse and worse, unable to do anything but pick them up when they collapsed again, putting them to bed, and give them their medicine.
Until a cure is found/Whumpee is cured. They make a full recovery.
Now Caretaker has to live with the memories. Still listening carefully when Whumpee showers, because they're so used to them fainting in the shower. Carefully watching them, worried they'll stumble again. Making sure they eat enough, even if Whumpee's appitite has returned again. Worried every single night, because Whumpee sleeping reminds them so much of how still they got, that they might not wake up again...