Sirius’s words are still hanging in the air when James blurts, “Wait—what?” His grin fades instantly, confusion flickering across his face as he looks between the two of you. “What do you mean born—?”

Then it clicks, and for a heartbeat, he’s silent. The room feels too still.

“Regulus…” he says quietly, eyes softening. “I didn’t—Merlin, I didn’t know. I just thought—well, I thought you were you.” He swallows, trying for a small, reassuring smile. “For what it’s worth, that’s all I see. You’re still you. Always have been.”

A beat, then he adds, voice barely above a murmur, “You alright, mate?”