This is an open bug that was archived. I am not sure if a new bug report is meant to be made.
Animal aging is turned off in options. Aging is turned off for all sims.
I have a save file I have played for a few seasons with another sim. I changed to a another sim family (an existing played family) that I have not touched for a long time and immediately Grim appeared and reaped a chicken. All chickens and the cow are aged to be "one...last...pet.."
Edit By Crinrict: Adjusted Title fit archived bug report: [NEEDS SAVES] [HR] [CD] [CoL] All animals aging up/dying (aging turned off) | EA Forums - 11612765
Generally bugs still open in the archive do not need to be re-reported unless you have new info.
