"What did you think of?" Dumbledore asked curiously.
"Back when Lupin and I were exploring, he told me a bit of obscure werewolf trivia: werewolves don't attack wild animals when they aren't hungry. And Lupin also knew Sirius's Animagus form, which meant Lupin and Sirius must have been very close back then," Kayson said in one breath.
Dumbledore nodded approvingly. "Go on."
"So Sirius might have learned to become an Animagus just to keep Lupin company when he was in werewolf form, so he wouldn't be too lonely. But was Sirius Lupin's only friend back then? I'm asking because I don't know much about their past."
Dumbledore nodded. "The four of them were very close friends. You already know about Lupin and Sirius. The other two were James Potter, Harry's father, and Peter Pettigrew, who had already died."
"That's it, then. Sirius probably wasn't the only one who learned to become an Animagus. I don't know the other two, but I know what young wizards their age were like. They could hardly stand being outdone in anything, so the other two probably learned Animagus transformations too," Kayson said quietly.
"Why are you taking this so seriously? James Potter and Peter Pettigrew had been dead for a long time," Dumbledore said softly.
"How did they die?"
"James Potter was found and killed by Voldemort at home. Peter Pettigrew was found and blown up by Sirius on a Muggle street. Sirius was sent to Azkaban because of that," Dumbledore replied.
"Why would Sirius kill Peter Pettigrew when they were friends?"
Dumbledore rose from his chair and began pacing around the office. "Back then, I cast a protective spell over Harry's home. That spell needed a Secret Keeper to take effect. As long as the Secret Keeper did not betray them, Voldemort would