Because if you look at their interaction in A NEW HOPE, the two seem to have a deep history with a very personal hatred for each other. And even beyond personal confrontations, Leia likely hates Vader because of the many friends and fellow rebels who have been tortured and murdered at his hands or at his instruction.

Why did Leia hate Vader?

She was raised on Alderaan and watched as it exploded. Moreover, her mother and father got killed during the blast. After that, Leia hated the Empire but really hated Darth Vader. So, when Leia learned that Vader was her father, it challenged her whole worldview.

Why can't Vader sense Leia?

Leia's Force abilities and her lack of awareness of her true identity also contributed to Vader's inability to sense their familial connection. Vader's denial of Anakin Skywalker's legacy and his fear of getting hurt again prevented him from realizing the truth about his children until later in the original trilogy.

What did Vader do to Leia?

Leia's ordeal. In the rough draft of Star Wars: Episode IV A New Hope, Darth Vader tortures Princess Leia with powerful electroshocks. In the incarnation of the second draft of A New Hope, Leia is replaced by Deak Starkiller, the brother of Luke Starkiller (who would become Luke Skywalker in later drafts).

How does Leia feel about Vader?

She finds it easy to accept Luke as her brother, but she is horrified by the idea Darth Vader was her father. Leia couldn't even understand why Luke accepted it so easily, and somehow believed there was good in their father.

New ‘Return of the Jedi’ footage CHANGES Darth Vader

Did Vader realize Leia was his daughter?

Darth Vader didn't learn he had a daughter until Return of the Jedi, when he stood before Emperor Palpatine. The Emperor's power probed Luke's mind, attempting to goad him to fall to the dark side, and he discovered Leia's existence. "Sister," the Emperor taunted.

Who did Darth Vader love?

Star Wars Just Confirmed Darth Vader's Undying Love for Padme Amidala.

Did Leia know Vader was Anakin?

Did Leia Organa ever find out that Darth Vader was her true biological father? Luke actually tells her in Return of the Jedi.

What did Vader inject Leia with?

One such droid was used by Darth Vader in his interrogation of Princess Leia Organa in 0 BBY. When Leia Organa underwent her mind probe, she was injected with a powerful mind-altering hallucinogen that made her very susceptible to suggestion.

Did Darth Vader love Padmé?

He eventually became so desperate to find a way to prevent Padmé from dying that his fear was ultimately the main reason that led to his fall to the dark side. Vader screaming for the loss of Padmé. Even as a Sith Lord, Anakin still loved Padmé very much, but felt great guilt for his actions against her.

Did Anakin ever talk to Leia?

In Star Wars Legends Leia was visited by the force ghost of her father Anakin Skywalker, the man who used to be Darth Vader. It wasn't a pleasant meeting as Leia was unable to forgive him for the things he'd done no matter how hard he begged, and it was the only time she saw him.

Why did Leia not become a Jedi?

After the Battle of Endor, Leia trained as a Jedi with Luke, but left the Jedi path after sensing it would result in the death of her son. She returned to the political arena, where the New Republic had reached an uneasy peace with the remnants of the Galactic Empire.

Did Vader really love Luke?

It was the fact that Luke was his son that caused turmoil within Vader. It was his love for his son that caused his loyalty to Palpatine and the Dark Side to falter. If Vader didn't know who Luke was he would have been just another force sensitive person to be trained to serve Palpatine like an Inquisitor or be killed.

Why didn't Vader know Leia was his daughter?

Leia was not using the Force or was currently Force-sensitive during her confrontation with Vader. She began training as a Jedi years later. All these reasons prove my point: Vader didn't know Leia was his daughter, and felt no presence of the Force in her, as she was not currently strong with the Force.

Did Palpatine know Leia was Vader's daughter?

She was not genetic Organa but still, she is rightful Organa. So yes, Palpatine knew that Leia is daughter of Anakin as well as the fact that Ben is the son of Leia and Han.

Why does KYLO Ren love Vader?

Darth Vader was revealed to be Kylo Ren's grandfather, with the latter having an obsession with the Sith Lord.

Did Vader ever stop loving Padmé?

Darth Vader Likely Hates Padmé

But there are moments in Marvel's other Darth Vader series that suggest that, while the Sith Lord is very much still obsessed with the idea of Padmé, her betrayal may have caused him to think ill of his late wife.

Why did Luke love Vader so much?

By the events of Star Wars: Return of the Jedi, Luke had accepted that Vader is his father, and his hatred toward his father had completely disappeared, transformed into love and hope, like his late mother, Padmé Amidala, Luke believed there was still good left in Anakin and that he could be redeemed.

Why did Leia name her son Anakin?

Leia and Han had three children, and they named their youngest son Anakin after Anakin Skywalker, Leia's biological father. Since Luke was the twin to spend more time with Obi-Wan in the old canon, it made sense that he, not Leia, was the one to honor Obi-Wan when naming his child.

Why didn't Leia forgive Anakin?

In Bloodline, Leia does sort of come to terms with Anakin/Vader. It is not forgiveness, really (this is the man who watched her planet get blown up, tortured her, tortured her husband, and was a known ruthless killer of dozens if not hundreds of people).