The Non-Canon Expert looks at whether Darth Vader was able to understand that it was specifically Leia who was Luke’s sister, and of course therefore his daughter, when he was able to sense Luke’s thoughts during their final confrontation in Episode 6: Return of the Jedi. This is a Legends story for Darth Vader and Luke Skywalker with information found within the Legends novels «Star Wars: Death Star,» «Star Wars: The Rise and Fall of Darth Vader,» «Star Wars: The Life and Legend of Obi-Wan Kenobi,» and the Episode 6: Return of the Jedi novelization.