It's always the creepy little kids
"Get me the sugar!" called Jack's wife. His heart skipped a beat as he stood before the cabinet. Holding his breath, he slowly opened it.... Dangit! A baby!
You receive a vision of a rooftop "somewhere close by", where a rare moss grows; in the vision, you know the moss is suitable for greatly enhancing the effects of certain types of potions. Now go and find that rooftop. Don't fall off. (Of course, rooftop runners *will* be taken for miscreants by the local City Watch....)