In the second teaser trailer, Luke says, “The Force is strong in my family. My father had it, I have it, my sister has it…you have that power, too.”

It didn’t appear in TFA, so maybe we’ll see it in VIII, and while it’s not definitive, it does imply a familial connection between Luke and Rey. (It’s clearly a new recording of Hamill’s voice, and my assumption is that it’s being spoken to Rey.)

It was kind of depressing to watch all the trailers again, because the trailers are excellent.