There are Happiness, Energy, Hunger and Hygiene stats.

They won't die, but if any of those stats are too low, you won't be able to take them out for walks around graal which is probably the most significant thing you can do with pets.

If their energy level is too tired, they'll just want to sleep. If their hunger stat is too low, their energy and happiness will start to drop. If you don't groom or wash them, they get all nasty and stuff and that will also affect their happiness.

Begs the question though. We have all these stats for pets but never have there ever been stats like this for ourselves. Strange.