Luke nodded. "That's him. He came because he recognized my last name. The Emperor'd thought that Anakin hadn't had children. I was a threat to his power."

As an 18 year old kid with three weeks of Jedi training. Some threat.

"So he sent Vader here to give me a choice." He bit his lip. "Last November he did. My choice was supposed to be joining the Dark Side or getting killed. I didn't really like those choices."