My sim is an elder- and besides grabbing dirty dishes and pouring it into a bake tray to make a new meal- they're pretty okay bug wise.
(strange behavior - for sure a bug, but i feel it adds a funny element to this elder sim so idc.)
However:
I've caught them walking through walls/walking through fences/walking across debug objects and over entire water features that are not interactable normally to sims --> to the edge of the map where they would have disappeared. (walking in a straight line)
I was able to pause the game and quickly type in [cas.fulleditmode] to Shift -->debug(reset object). before they disappeared into a mountain range and I'd be unable to find them. It did teleport my sim back into their house however I was worried this would be a reoccurring problem for this sim.
I do have images of this saved via [C] to capture this happening - this was in Newcrest, near the twin points(?) smt property.
(by the kids pirate ship playstructure/gyser that's fenced off - there are no fishing locations on this side of the map just sidewalks).