The Mists of Huron Court - A Foxglove Corners Mystery, #21

The house was beautiful. a vintage pink Victorian in a picturesque but lonely country setting, and the girl playing ball with her dog in the yard was friendly, suggesting that she and Jennet walk their dogs together some time. Jennet thinks she has made a new friend, until she returns to the house and finds a tumbling down ruin where the Victorian once stood and no sign that the girl and dog had ever been there.