The Potter house smells like clean linen and chocolate, curtesy of the cake Remus baked as a well done present for Lily. But Sirius barely notices, his attention is fixed entirely on the impossibly small bundle in James’s arms, wrapped in soft blue and making the tiniest, most offended little noises.

“That’s him?” Sirius asks, stupidly, because of course it is. James’s grin is carved into that tiny face already, unmistakable even at a few days old.

James snorts. “No, mate, we borrowed a random baby from the ward for a laugh.”

Lily rolls her eyes from the sofa, colour finally back in her cheeks after the hospital, though she’s still propped up with cushions and watched like glass about to crack. “Give him the baby before he vibrates out of his skin.”

Sirius freezes. “Me?”

James steps forward carefully and places Harry into Sirius’s arms. And to Sirius, the world stops. Harry's tiny fingers curl reflexively into the fabric of Sirius’s shirt, gripping like he knows exactly who he’s holding onto. Sirius stares down at him, grey eyes gone wide and bright, breath caught somewhere painful in his chest.

“Hi Harry,” he whispers.

Harry blinks up at him, as perplexed as a new-born can be by the sight of a new face.

James watches the scene for a moment, smile fond, then he clears his throat in a way that’s far too deliberate. “So,” he says casually, “Lily and I were thinking-”

“We already decided,” Lily cuts in sweetly.

James grins wider. “We already decided. Sirius... you’re his Godfather.”

Sirius doesn’t react at first, he could only blink. Then his breath shudders out of him like he’s been punched clean through the ribs. He looks up sharply, eyes flicking between James and Lily, as if waiting for the punchline.

“You’re joking,” he says hoarsely.

James shakes his head, suddenly softer. “No one we trust more. Well, except Remus. He'll be baby number two's.”

Sirius looks down at Harry again, and something fierce and bright cracks open in him. Like it did the first time he held Regulus. He turns his head slightly, his expression is pure disbelief, joy unmatched. "Am I dreaming?" Sirius murmurs softly, "You hexed me before we got here and I'm dreaming."