There're a few bits from the earliest announcements of DOS that might give us a clue:
  • The original name for the game is 'eyes of a child'
  • The original background for Rodderick was to be someone who was tortured.
  • The original background for Scarlett was to be someone who was resurrected from death
Altough that information is possibly out of date, considering there's no obligation to have 2 male or female characters.