" Even houses change, Reynie had thought, and it had caused an odd flutter in his stomach. Weren't houses supposed to represent stability? Sure, the Society had changed a lot of things about Mr. Benedict's house on purpose, but some things, Reynie realized, they had changed simply by being there. A thousand footsteps on that particular board, and now it creaked.
Every member of the Society, too, bore a thousand hidden footsteps: effects of a different kind, many impossible to have predicted. "
― Trenton Lee Stewart , The Mysterious Benedict Society and the Perilous Journey (The Mysterious Benedict Society, #2)