Darth Vader may never have known that Princess Leia was his daughter in starwars and that he never had a relationship with her, not even when she was a Force ghost. Anakin Skywalker never knew that Padmé was pregnant with twins and believed that his child had died with his wife.
He had no idea that Padmé had given birth before she died, let alone that the Jedi had taken the children and hidden them. the illusions of Darth Vader they broke up shortly after the destruction of the first Death Star.
And Vader held himself responsible for the Empire’s defeat on Yavin 4, seeking revenge against the Rebel who fired the shot. He hired bounty hunters to scour the galaxy looking for him, and Boba Fett ended up returning under the name Skywalker. It was then that Darth Vader realized that his son was alive, and began searching for him.
Darth Vader he didn’t find out he had a daughter until Return of the Jedi, when he presented himself to Emperor Palpatine. The Emperor’s power probed Luke’s mind, attempting to lure him to the dark side, and he discovered the existence of read. “Sisterthe Emperor said to himself.So… you have a twin sister. Your feelings have now also betrayed her“.
Luke reacted with a flare of rage, finally flicking his lightsaber, and soon Luke and Darth Vader dueled. Surely the mind Darth Vader he was going full speed while fighting, and it is possible that he deduced the true identity of the sister, since he knew that Luke and read they had been working together for the last few years.
Maybe read initially trained as a Jedi, but never desired a relationship with the Force ghost of Anakin Skywalker. Claudia Gray’s novel Bloodline states that Leia struggled with the knowledge that Darth Vader was her father, as her memories of the Dark Lord of the Sith were the stuff of nightmares.
He was unable to forget his experience on the first Death Star, when Vader had tortured read in an interrogation in the hope that he would reveal the location of the rebel base. Leia didn’t know if she could withstand a sight of Anakin Skywalker’s Force ghost.
There is evidence that most Jedi need to train themselves to see Force ghosts, and Leia’s attitude towards Darth Vader may well have meant that her father was unable to appear before her.
Unfortunately, while Leia managed to process many of her emotions towards Anakin Skywalker, there is no evidence that they cultivated a relationship through the Force. Rae Carson’s novelization of Star Wars: The Rise of Skywalker revealed that Force ghosts had guided Leia on occasion, even before she returned to the Jedi.
He had occasionally heard Obi-Wan Kenobi’s voice, and even more rarely Master Yoda’s, but he never seems to have seen Anakin Skywalker’s Force ghost.