In this 6 th book by Cindy and Gus Gee, Mom shooed Boar, Junior, and Hardy out of the house and told them to play outside. As the kids wandered around the backyard, they spotted a big tree. The kids thought it would be cool to build a treehouse on it. But how? Hardy then remembered a story Dad once told the kids about making tin-can telephones when he was kid. You will laugh as you watch the kids figure out how to build their treehouse.