It'll just happen sometime. One of your little peeps will be sick and when you try to cure them, they'll just keep getting sick again and again and again. Then when you finally pay for the doctor's checkup, you'll find out that they are "gravely ill" and that you have to buy the Vancomycin (or whatever that shot is called, lol!) and then you'll get that trophy. It's happened to me twice and I really do try to take good care of them. So, it just happens is all, nothing you can do to make it happen. Well, not that I know of anyway.