Yeah I have an aunt who does it for a living as well and family paid and arranged for her to take care my grandmother (dementia and some other general health failing issues from being old and having had knee and hip replacements). Could see it exhausted her pretty quick even though she's used to it because it's one thing to be doing it with a 'stranger' you may learn to care about but it's another thing to do it with family.

She managed to keep it up for a bit over a year but then couldn't manage it any longer and had to move grandmother to a home with 24/7 care.

This is why you'll never find me jumping on any of the band wagons I've seen on reddit where people try to shame family members for not taking care of their elders and the like; it's really not feasible. Yeah maybe people did so 'back in the day' but back then people didn't typically live this long especially with the amount of health issues that we can keep people alive with. There's also nowhere near the same size families to offer that care and most adult family members work away from home now rather than have things like stay at home wives and the like.