Now, it was really physically impossible for Billy to correctly identify just who was falling over on the stairs simply by the noise they made, especially since he wasn't paying full attention until the kind of crashing-thumping noise jogged him out of his daydream. But he just had this all too familiar sinking feeling in the pit of his stomach that it was Tommy, and he'd done something stupid, and then there was the sigh and yes, that was definitely Tommy sighing. Falling over on the stairs and sighing.

Billy hopped up and ran out to check just what was going on. "Tommy! What happened?" He hopes Tommy appreciates his generosity in not saying what have done now?, since that would be equally valid. He's tipped towards what he actually says, though, by how pale his twin looks.