The ElseWhere Chronicles 4: The Calling : Book Four

After escaping from the Master of Shadows, Max, Rebecca, Noah, and Theo try to return to their ordinary lives in the ordinary world. But they can't forget the villainous creatures that threaten the world they left behind on the other side of the Shadow Door. All is not well at home, either. When Rebecca falls dangerously ill, the only cure may lie in ElseWhere. But how can they get there, now that they've destroyed all of Grandpa Gabe's passageways?