What are the motifs in Heaven Is for Real: A Little Boy's Astounding Story of His Trip to Heaven and Back by Todd Burpo?

Faith was a key element in this book. The Burpo family remained faithful to God even when they dealt with the harsh blows life threw at them. This did not mean that they accepted everything passively. In fact, there were several times when Todd lashed out at God. But he never turned his back on God.