Michael Buckley 
Problem Child 
The Sisters Grimm, Book Three

In book three of the series, Sabrina and Daphne Grimm tackle their most important mystery: Who kidnapped their parents more than a year ago? Sabrina enters the hideout of the Scarlet Hand, the sinister group of Everafters who are keeping her parents prisoner. She has a chance to rescue her mom and dad but is foiled by the most famous fairy-tale character in the world. With the help of her little sister (who might be tougher than Sabrina realizes) and a long-lost relative, Sabrina finds a powerful weapon for fighting her enemies, and discovers that magic has a high price.