Why did Ellis write the book?

In an interview, Ellis answered this question fully....

After I finished my last two books, on John Adams and Thomas Jefferson, I realized that I had read much of the correspondence produced by the founding generation. I did have to go through the Washington letters, and read the Burr correspondence, but otherwise I had pretty much started a new book on the entire group of founders without quite knowing what I was doing. And throughout those letters, they kept referring to each other as a "band of brothers." We think of them as Founding Fathers, but they saw themselves as a fraternity. I should add that my title fails to include the one sister in the group, Abigail Adams, whom I think was an equal partner in her husband's political career.