"I hate that I wasn't there for you like I was supposed to be," Sirius said after a long moment of silence between them. "They trusted me with you and I was supposed to be there when they couldn't be. I'm sorry -" If Sirius was getting choked up a bit, he masked it fairly well with another loud, barking cough as he stood up and paced away from Harry. He stood with his back to him.
"I'll talk to him," he said shortly, shoulders slump. "You shouldn't have to tell him what happened. I'll do it."