Episode 69 of "Sabrina, the teenage witch"
s03e19 The Big Sleep
Title: The Big Sleep
Original Air Date: 03/12/1999 on ABC
Plot Outline:
Searching for clues to the family secret, Sabrina calls up Aunt Dorma, the "black sheep" of the family, accidentally waking her out her usual ten-year nap -- and Dorma retaliates with a household of magic poppies fatal to Spellmans.
