Hills kitten food made my kitten sick!

Hills Science plan for kittens (chicken) made my kitten very sick. Every time I fed her the Hills she had severe diarrhea, after I fed her chicken and rice boiled in water she was fine. The very next day when I gave her the Hills again same story, even a teas**** of the food gave her diarrhea. After several days and too many times of washing my kitten I had enough. I took the food back to the vet and they said Hills will phone me. To cut a long story short - My kitten is now on Royal Canine for Kittens.