That does seem awfully young to have stained teeth. I was told to brush my cat's teeth however I value my fingers so I don't bother. My cats are 17 and 11 and the 11 yr old has gone in twice to have toofies cleaned. I will not do it for the my 17 yr old. Why kind of wet food? I've been told that the cheap wet food such as Friskies contain some dye and I wonder if that is causing the problem.