The debate over whether “Harry Potter” character Severus Snape was loyal to Dumbledore or Voldermort has raged on for years, but book-series author J.K. Rowling gave the late actor Alan Rickman a hint about the complex character. She revealed the answer to her 6.5 million followers on Twitter Sunday.

“Will you tell us the piece of information that you told Alan Rickman about Severus Snape? Or will that forever be a secret?” one commenter questioned. Rowling, 50, then answered: “I told Alan what lies behind the word ‘always.’”

At the end of the books, Snape and Dumbledore discuss the reason Harry Potter was kept alive. He answers the question with the word, “Always,” which could have different meanings.

This is how the conversation unfolds in the film:

“So when the time comes the boy must die?” Snape says.

“Yes. Yes. He must die,” Dumbledore replies.

“You’ve kept him alive so that he die at the proper moment. You’ve been raising him like a pig for slaughter,” Snape says.

“Don’t tell me that you’ve grown to care for the boy,” Dumbledore says. “After all this time?”

“Always,” Snape answers.

In the book, however, it unfolds a little differently.

“But this is touching, Severus,” said Dumbledore seriously. “Have you grown to care for the boy, after all?”

“For him?” shouted Snape. “Expecto Patronum!” From the tip of his wand burst the silver doe: She landed on the office floor, bounded once across the office, and soared out of the window. Dumbledore watched her fly away, and as her silvery glow faded he turned back to Snape, and his eyes were full of tears. “After all this time?”

“Always,” said Snape.

Whether it’s the book or film version fans prefer, it all boils down to one thing: Snape’s love for Harry’s mother, Lily.

The answer to “always” is what helped Rickman better understand the Hogwarts potions professor he played in the series. “[It] helped me think that he was more complicated and that the story was not going to be as straight down the line as everybody thought,” the actor told Hit Fix in 2011, according to Us Weekly. “If you remember, when I did the first film, [Rowling] had only written three or four books, so nobody knew where it was really going except her. And it was important for her that I know something, but she only gave me a tiny piece of information which helped me think it was a more ambiguous route.”

Rickman died of cancer Thursday. He was 69 years old.

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