Since the Force Awakens, cynics of the new films have bitched about how Rey received Jedi powers pretty much out of nowhere. And The Last Jedi pretty much explained that Rey isn’t the long-lost child with rich Jedi ancestry; she’s just a random orphan. A new Darth Vader comic helps explain how Rey ended up with Force powers. It’s simple, it’s the Force’s way.
In Darth Vader #10, we see the Sith Lord face off with one of the few Jedi to survive the purge in Episode III, Jocasta Nu, an older Jedi who was chief librarian of the Jedi Archives. While they duel, Jocasta tells Vader that he is little more than a pawn Emperor Palpatine is using in an attempt to snuff out the Light side of the Force. That’s impossible, she explains as they battle.
“The Force is eternal. I cannot be ended, it cannot be stopped, no so long as life exists,” she says. “It will find its vessels. It always does. It already has — you know this. There are others, waiting out in the galaxy.”
A perfect example of this happening is Anakin Skywalker, he himself was a vessel.
If you notice in the image above, Jocasta says the Force “already has” found vessels, and that “there are others, waiting out in the galaxy.” Rey hasn’t been born at this point, so those existing vessels are probably Luke and Leia.
If you think about it this can also explain the child at the end of The Last Jedi. The vessel could be anyone and anywhere.