My sim has some pets that I specifically want to turn aging off for, so I clicked on those pets and in DebugEnabler I clicked Aging - Toggle Aging. On first glance it seemed to work, because on the pet it showed "Days till age up: Never". However, a couple of in game days later proves it doesn't work, because by then they will have aged a couple of days and the 'never' part is gone too. I also read about setting it in StoryProgression, with the Sim - Death: Disable Aging" setting, but when I choose that and go to their age bar it still says "age up in x days". I don't want to disable aging for all pets, because I want the other pets in the world and the foals/puppies/kittens my main pets get to age normally. So, is there a way that does work for this? Thanks!

I have never done this with DE, but I do with Storyprogression by clicking my pet sim and never had problems with it.

It may take a while when you first change this. Maybe save, quit game and start again

Hmmm. Maybe it does the opposite from the DE setting. Working but not showing it at the age bar. I will give that another go then, thank you very much!

The game clock needs to run for a while before this setting will be reflected in the UI, but it should definitely be done with StoryProgression. It's normal for it take a while to refresh.

DE should only really be used for troubleshooting and fixing issues when it has been specifically recommended. My understanding is that it's just an interface to access EA's own developer cheats, I would not use it to enforce a mechanic like this. Especially because SP will still be trying to manage aging according to its own rules