When you are publishing a book with descendants of a common ancestor, keeping everyone straight is a challenge. There are several numbering systems that greatly assist the reader (and you) to know how each person is related. The one that I like the best is called the d'Aboville number system. It was developed by Count Jacques d'Aboville in 1940. It start with the common ancestor being number 1. The oldest child of person number 1 is given the number 1.1, the second child the number 1.2, and so on. In the third generation, the oldest child of person 1.1 is assigned the number 1.1.1, the second child of that person is 1.1.2, and so on. The oldest child of child number twelve is 1.12.1, the second child 1.12.2, and so on. It is an simple system to learn and to follow from generation to generation. Here is a sample of what it looks like in the book.