I beat the warehouse, talked to Willis and heard the dialog about the path West being open, went to the store, bought some stuff, but I can't figure out how to proceed. Whenever I go to the mines or sewer, I just get forced back out because the kids couldn't have gone that way. I've scoured the city, completed the bonus levels, but I'm still stuck. Willis and Arlene are the only ones left alive. Arlene is still talking about finding the warehouse key, by the way, which is a bit strange considering what has transpired.
Anyway, I'd appreciate someone telling me the way forward.