"Ah, now that changes everything!" Brightening immediately, the old wizard began to rummage in his robe's sleeves and pockets. "If someone has seen her, then it is indeed likely she is already here!" Dumbledore would not exclude entirely the possibility that someone was playing a cruel joke on Rat, but he did know the school tended to suck in groups of people from the same world, sometimes from the same family. "Would you care for a chocolate frog?"