2011: Demi wins Favourite TV Guest Star for her role in Grey's Anatomy at the People's Choice Awards This image appears in the gallery:33 Pics Charting Demi Lovato's Transformation Through The Years 15. 2011: Demi wins Favourite TV Guest Star for her role in Grey's Anatomy at the People's Choice Awards 33 images See the full gallery: 33 Pics Charting Demi Lovato's Transformation Through The Years