Honeychile, that's the one. I not only remember it, I have it on video (Yeah, I know, take away my man card now
). Two sisters go to college, one joins the popular group (Alpha Nu Sigma) and the other the "spooky" (Phi Epsilon Delta = nicknamed Pigs, Elephants and Dogs by ANS) house. Spooky house sister goes all "Carrie" on the popular house after they pelt her with mud and rotten tomatoes. Add in Shelley Winters, Morgan Fairchild (as the b****y popular sorority girl), a demon dog, then get some popcorn and let the good times roll!