Who Knew There'd Be Ghosts? (Hardcover, Turtleback School & Library ed.)

Townsfolk walking by the abandoned Parnell mansion tend to quicken their steps - especially if night is beginning to fall. But to Tommy and his best friends, Books and Harry the Blimp, the old house is the perfect playground for their imaginary games. Then one night the three friends overhear a stranger's plans to destroy the house in order to find its hidden treasure. There must be a way to save Parnell House - but what can three kids do? Luckily, they have help. Two Parnells still live there - two Parnells who happen to be ghosts!