If Sirius would have heard the story any other time, he would not have believed it. But after finding out that Peter was a traitor the thought that Regulus was also one did not seem so impossible anymore. Slowly and barely visible he shook his head. His brother stood on the same side as Sirius. A part of him wanted to believe it and another part just couldn’t. This wasn’t the Regulus he knew.
“Why didn’t you come to me? I could have helped!” Sirius said, his voice full of confusion and anger.