Spoilers for the final season of LOST below.
In the flash-sideways universe, Jack and Juliet have a son named David Shephard. Unlike other major characters of that world, he has no known real-world counterpart. He does not move on with the other characters at the end of the finale.
So who or what was he?
- Was he an entirely fictional construct of the shared flash-sideways reality?
- Was he some other people's son in the real-world, and "given" to Jack and Juliet to help them gain closure?
- Was he actually Jack and/or Juliet's son in the real world, somehow?
- Or was he something else?