The sound was wrong. Not the usual destructive chaos I'd grown almost immune to, but something wetter. More determined. I set down my coffee—black, two sugars, the mug my sister gave me with the chipped rim—and walked into the living room. There he was. My eighty-pound golden retriever, Finn, sprawled on the beige wool rug my grandmother handed down to me, tongue lapping furiously at the kitchen floor like he was trying to taste through the linoleum. His tail thumped once, twice, a lazy acknowledgment of my presence. He didn't look up. He never looks up when he's locked onto something. I crouched down and saw it. A smear of something brownish, vaguely peanut-butter colored, spread across three floor tiles. Finn's tongue worked the grout lines like he was mining for gold. And that's when I remembered the jar of xylitol-free peanut butter I'd left on the counter that morning. The one I'd used to make myself toast before work. The one I'd meant to put ...