Yes, I've heard that animals also go through a grieving process just like we do. Since Corkscrew was very close to Zasper he may also have a hard time. This may have been his way to help you ease your sorrow and pain. You may eventually need to get another cat for Corkscrew. Once again I'm so sorry to hear about your loss and my prayers go out to you and Corkscrew to help ease your pain.