Death

I play one household and let everything else happen through progression (via a mod). That household is immortal. Every other household suffers the consequences of aging, illness, and accidents.

In real life: All of the above except for "fun."
In game: Death? What's death?

It is a part of life, which is why I don't prevent it from happening, but I am always sad to see them go.

Can't really pick an option because for me it's kinda all of them. Sometimes in the Sims death is fun (I might even deliberately seek it if I'm bored), sometimes it's sad when I'm letting go of a dear old sim, sometimes I avoid it altogether (like turning my favorites to vampires i.e. immortals, or reloading a save if i somehow managed to get them killed) and sometimes it's just a normal part of life which happens when it happens whether due to an accident or natural causes.

Early on, it made me really sad, but a couple generations in and I've kinda grown numb to it.

Aye I let my sims die as a legend once sang who wants to live forever, I wouldn't want to live forever eventually I would get fed up tbh, with my sims too ? the idea of immortality sounds torture for me in real life and In the game lol

I guess it's really all of it depending on the save but yeah I get attached to certain sims and it can be sad but it's nice to remember them...other times even sims I like can get on my nerves so you know Grimmy can be the watcher's favorite pal.