In a grimy alleyway in London, Sirius and Bellatrix appeared, Harry held close in the man's arms.
"Where are we?" he asked shortly, backing away suspiciously.
"Muggle London. There's a hotel about a block down," she answered. He looked at her for a few moments, searching for signs of betrayal, then relaxed.
He transfigured some spare bits of paper into muggle money, and Bellatrix quietly confunded the owner as they paid for the room. They - or rather Sirius; his cousin didn't have a clue how to do it - changed Harry's diaper and put him in pajamas, and after they cast a sound-dampening charm over him to cut out the noise of police sirens and car horns, he fell off to sleep quickly.
Sirius didn't seem to want to talk, or perhaps he wasn't able to. Distant, he sat on the edge of the bed, watching Harry sleep. Finally Bellatrix interrupted the silence.
"His father was James Potter, wasn't he?"
"Yeah." Sirius' attention returned to the present. 'He's been under the Fidelius spell for a while now - " he broke off abruptly and stood up. "Peter, you bastard!" he hissed, and strode to the door.
"Wait, Sirius, where are you going?" Bellatrix asked with alarm. Her cousin turned around, keeping his hand on the doorknob.
"Do you remember Peter Pettigrew?"
"Yes, he was the fat guy, part of your group at Hogwarts, right? Why?"
"He was James' secretkeeper," confided Sirius angrily. 'He must have given James up - I'm going to rip his little ratty head from his shoulders-" he turned to the door again.
"Wait - you have Harry to take care of!" pleaded Bellatrix.
"And Harry doesn't have a mother or father, thanks to that scum!" growled Sirius, turning about. "Peter deserves to pay - "
"And then what will Harry do?" Bellatrix sneered. "A dead mother and father and nothing to remember them by - a murderer for a godfather - who's going to take care of him then?" she ranted, almost yelling. Sirius stared at her for a moment, then turned and punched the wall, hard.
"Why? How could he?" he screamed, and hit it again, then again and again. Bellatrix stood by awkwardly, not knowing what to do.
"Why?" he cried again, falling to his knees and hitting the wall one last time. His fist left a smear of blood on the wall, and the darkhaired woman sucked in a breath, then, pulling herself together, knelt and put her arms around him.
"Why..." he asked again, and the tears began to fall as his knuckles bled thickly onto his worn jeans. Bellatrix sighed.
"Siri - " she used the nickname she had called him when they were children, hoping it would calm him - "It can't be changed - it's over and done, and you have Harry to think of now," she said, helping him stand up, then backing away. Siriuswiped his face with his sleeve, looking away quickly to Harry.
"You're right," he said after a moment, glancing at her. "It won't change anything." He looked down at his knuckles, still bleeding slightly, and rubbed them clean on his jeans without flinching.
"I'll be back in a while," he said, and was out the door before Bellatrix could protest. She laid down next to Harry and watched the rise and fall of his tiny chest for a long time, thinking of death, and friendship, and things which cannot be changed, but can be atoned for, and the right thing to do.