Sirius cocked up an eyebrow in disbelief. Since when did his brother care about him? Before he ran away Regulus had never backed him up against the rest of his family. He had never done anything that could have suggested that he did not share his parents’ beliefs or that Sirius’ welfare was something he cared about. And now he suddenly did?
“You know that I am already on the list of Voldemort’s main targets. If you haven’t noticed: I’m a blood traitor. Death Eaters don’t exactly line up to congratulate me on my choice of company. And Dumbledore could have protected you. Because that’s what we do, we help each other”, he told him, angry that Regulus had been too dumb to recognize this.