Boot's Bridge (Gabe and Abby Adventure Series) (Volume 1)

Gabe and Abby are kindergarten aged twins on a summer camping trip with their family. They're pretending to fish with their toy fishing poles at the edge of a pond near their tent, when one of their hooks snags a boot. The content of that boot starts an adventure in which the kids become heroes when they rescue one of God's wonderful creatures, nurse it back to health, and release it. The park ranger on duty sees the whole thing and renames a park hiking bridge to honor a "new best friend" of the twins.