about 6months ago my cat died, but im not sure how she died. i came home and gave her some food and she was perfectly fine and i went inside. i came out about 5 minuets later and she was vomiting, her eyes were darting from one side to the other, her head was shaking and her back legs seemed paralyzed, we rushed her to the vet where she stayed overnight, she stayed there for about another 5 days and passed away overnight one night and they never found out what happened to her, any ideas?