The Spellman Files is one very fun book. The Spellmans are a family of private eyes: the parents start the kids on background checks and simple surveillance at an early age. Naturally, they use the techniques at hand to handle family issues -- e.g when Mom wants to check out our heroine Izzy's new boyfriend or when Izzy wants to dodge said surveillance. The youngest child, Rae, the real star of the story, finds recreational surveillance a great game, and a new telephoto lens the perfect gift. The oldest, David, has managed to escape (more or less) to a career as a lawyer, but when he explains to a young Rae what he does ("negotiate"), he adds blackmail as another useful tool to the family's arsenal of dispute resolution techniques.
Only the thinness of the plot kept me from awarding a star to this very original and entertaining addition to the mystery field.