There are a host of reasons authors write books -- to tell a story, to push a message, to bolster their egos, among others. Hannah and I often are asked why we decided to write The Power of Half as the chroniclers of our foursome's journey.

So, I put the question to Joan and Joseph, and here are our family's main reasons.

1. About six months into our project, we grew increasingly aware of how our efforts to give were strengthening our family. We began to feel strongly about the benefits other families or communities could reap by joining together for a common purpose. So, we felt moved to share our story and methods. In other words, maybe we could help other families be stronger too -- and help the world a little in the process.

2. When we decided to do a "half" project, we couldn't find the stories or methods of others; we had to invent the process ourselves. As a result, we stumbled and wasted time. We wrote The Power of Half because we felt we could create a roadmap for others who wanted to pursue their own "half" projects.

3. During our journey, we met some amazing and inspiring people. The characters in our family's drama -- from John Coonrod and the entire staff of The Hunger Project to our housekeepers, Hector and Rosie -- played a vital role in our transformation. Writing the book was one way of giving shape to our gratitude to them.

4. We wanted to keep the spirit of the project alive for our family. After we had sold the house, chosen The Hunger Project as our partner, traveled to Ghana to visit the villages, and settled in to our new smaller house, there was little more of the project to do on a daily basis. Writing the book prolonged our project, and provided new ways for us to be creative together.

5. I write for a living and I think it's a pretty honorable profession. We will use the proceeds from the book to make up the shortfall between what we pledged to The Hunger Project and what our house sold for. And, of course, we'll use a chunk of the money to continue funding the organizations we believe are doing great work in our local and global communities.

Thanks for asking.