In the Emperor Strikes Back, it didn't make much sense during the scene where Luke takes off on his X-wing. Obi-Wan : That boy is our last hope. Yoda : No, he is not, there is one more. One more?? who?
Yoda says "There is another." ROTJ: Luke - "Yoda talked about another." Ben - "The other that Yoda was talking about was your twin sister."
I am sure there is a recent topic about this . . or maybe more than one And Yoda's talking about Leia
Its very clear if you watch ROTJ. Just for some extra information I read somewhere that in the early ESB drafts this line was supposedly created because luke was going to fall to the darkside and 3 other movies where going to tell the story of another jedi rescuing Luke and Anakin from the darkside considered at some point before GL decided that Leia and Luke where twins. I don't know if this is completly true but I remeber reading it as an answer to a post a couple of years ago here on the forums.
sergejg: I've heard about that too, years ago . . .I even had forgotten about it. But there's a moment when Luke has been defeated by Vader and he's hagning at end of Cloud City and he calls Leia with the force and she feels him that makes the revelation of them being twins not that far fetched . . . I remember I saw the trilogy for the first time on tv on three consecutive weekends when I was like 7 (probably 88, or 89), and since then, I've always looked at that scene on ESB like a connection to that revelation in ROTJ. . . like if it was thought before ROTJ . . . . but then of course, there's that scene were Leia kisses Luke on ESB . . . . . . . . . . . . . weird ****
"How can Leia bring balance to the force if luke fails?" She's a Skywalker, the force is strong in her.
Strong, if untrained. Palpatine and Vader even discussing trying to turn her to the darkside, if Luke won't join them (and is killed as they assume). All the while DV's plotting to use Luke to kill the Emperor and the Emperor's planning to replace Vader with his uncrippled son (well, apart from a cyborg hand, but Anakin had one too before Palpatine turned him). She was pretty good with a blaster, but it would've taken some time to train her to use a lightsaber... By that time the Rebellion would've been in serious trouble, given that they wouldn't've been able to train Leia in secret.