Squirm by Carl Hiassen
Billy hasn’t seen his father, Dennis, since he was three. His mum refuses to talk about him and Dennis is a huge mystery in Billy’s and his sister Belinda’s lives. When Billy is finally able to find his dad’s address, despite his mum’s best attempts at hiding it, he steals his mum’s credit card (leaving her a cheque for the amount stolen) and buys a plane ticket from Florida to Montana to find his dad. When he finally arrives he is greeted by his stepsister, Summer, a First Nations American from the Apsáalooke Nation (AKA the Crow Nation) who informs him that his dad is off on a mysterious ‘mission’. Together, Summer and Billy are determined to find out where Dennis goes when he disappears into the wilderness.
Billy and Summer enjoy Enid Blyton-levels of freedom in Squirm (though not always approved of or signed off on by the adults in their lives!) and though they trek about unaccompanied by adults in both the Floridian and Montanan wilderness, they are very sensible about it, even when danger strikes. In this way the book is reminiscent of old adventure stories like Hatchet by Gary Paulson. Squirm is a refreshing and fun story for kids 10+.