The first episode to feature the past lives of the main characters.
Phoebe's date of birth is November 2nd, 1975. Piper's is August 2nd, 1973. Leo's past life (which Anton impersonates) dies sometime between February 17th, 1924 and May 6th, 1924 as this was around the time Leo was born.
Greg Vaughn (Dan) and Tyler Christopher (Anton) went on to play half-brothers Lucky and Nikolas on General Hospital.
French: "Soeurs contre soeurs" (Sisters against sisters)
What Could Have Been: The script initially had the first names of the Halliwells' past lives, but producers felt this would be too confusing for viewers. They're only known by the first initial and last names in the episode, and not called by their names at all.