HP - Riddle Me This

Upon gaining possession of the Philosopher's stone, circumstances force Voldemort to take up the mantle of Lord Slytherin. How does he intend to fulfill the requirement of having two Parselmouth descendants of Salazar Slytherin? Why, by abusing time travel to bring a soon-to-be eleven-year-old Tom Riddle from 1937 to 1993, of course. Enter transmigrated character, Edmund Cole. M/F