When my sims were visiting Salty Paws Salon, they saw Catarina Lynx's cat Cleo at the docks with the "Stray" label over her head.
I thought it was just a lookalike, but when I checked the screenshot I'd taken of Cleo at her home, the stray looked exactly like...even the same kind and color of color.
So then I checked Manage Households to see if Cleo had disappeared from the Lynx household but, nope, she's still there.
Do pets temporarily stray from home? Could my sims have adopted Cleo away from Catarina? (which I wouldn't do because Josie is my favorite...).
I guess I should actually commit myself to a new game with pets instead of just dabbling...