If you can find it (since it’s now out of print), snatch up King of the Cannibals: The Story of John G. Paton by Jim Cromarty. It is a fantastic biography for children. It’s easy to read (third-grade reading level), full of adventure, danger, and excitement, and is beautifully interwoven with spiritual lessons that strengthen faith. In moments of personal trial, I often remember John Paton sitting up in a tree on that South Pacific island, cannibals with guns searching for him on the ground below. On that occasion of great danger (one of many in his life), he said that he had a wonderful experience of communion with Christ. Up in that tree, Jesus calmed john Paton’s anxious, frightened heart, bringing to mind Matthew 28:20: “And behold, I am with you always, to the end of the age.”
It looks like there are some inexpensive used copies available on Amazon.