Recent research shows that after a fight, chimps and bonobos and gorillas “often follow confrontations with friendly behavior like embracing or kissing.” Even hyenas will approach those that have angered them and make up through conciliatory gestures. The only animal that doesn’t seem to forgive is a cat.

That means if you anger a cat, that cat will likely harbor a grudge, despite the fact that grudges are bad for you. Apparently cats have nine lives so they can harbor a grudge and still stay alive to continue harboring it long after the incident has passed. As a general rule, don’t upset your cat. You don’t want to know what might happen if you do.

To read more about how cats don’t forgive, click here.