The problem showed itself at dinner. Lily tried to tell a story about a lost key to her art box—the one with her grandmother’s old sketches inside. Sam interrupted. Mrs. Green checked her watch. Mr. Green took a call. No one heard.

The Green family had a problem. Not the usual mud-on-the-carpet or fighting-over-the-remote problem. This one was quieter but sharper:

Nanny McPhee rapped her stick once on the floor. The table fell silent.