Is there some moment in The Empire Strikes Back when the lightbulb goes off over Darth's helmet and he has that "Ah-Ha!" moment?
Or is it offscreen between Star Wars and Empire, with the audience left to decide whether Darth sensed it via the Force, or figured it out once someone told him the DeathStar-destroying X-Wing pilot's last name was Skywalker?
If it's through some force-sensitivity, is there any explanation ever given for why Vader doesn't realize Leia's his daughter, even though they come into contact with each other several times? It might have made a difference when it came time to torture her for information. In fact, if Vader's so strong with the Force, I think he should have realized the connection during their first conversation ("You are part of the rebel alliance and a traitor ...... oh, and my daughter!")
Is there something I'm missing from the movies about Darth Vader's faulty dad-dar? Is there anything in the EU that sheds light on this subject? Or do you have any personal, wild theories?
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