"That's not what I mean," Sasuke started, annoyance creeping into his tone, but he shut up when Itachi continued to give an actual explanation -- for once, acting as if Sasuke were someone more competent than a baby brother. On another occasion it might have been cause for a swell of pride, but he was far too occupied with concern to get lost in it.

"It might just be a longer-term infection," Sasuke said, though he sounded dubious himself. "But with T-cell counts low ..."

Abruptly, his voice grew irritated, picking a quick target: "If cousin didn't constantly send you out for weeks at a time, we'd have a better idea of whether it's one long infection or something else."