Here is some inof on her character from TV Guide:
Maiara Walsh, who played Gaby’s and Carlos’ bratty, over-sexed niece Ana on last season’s Desperate Housewives, is headed to Mystic Falls to cause more even trouble. In Vampire Diaries’ Oct. 7 episode, the 22-year-old actress will appear as Sarah, a high schooler who likes to party. Woo-hoo! Crack open the coffins and pour me some blood!
Get more info at TV Guide.