From the Preface -
I would say probably from around 2003 to 2005, around the time we moved into The Mirabella, I began to lose my memory and I felt that I didn't have enough memory to proceed with my memoirs. I really didn't do anything about continuing them except to include an account of our trip through Africa. That was because Irene had written a book about it, so I was able to read the book to refresh my memory. Because I found that my memory was failing me, I got Irene to help me with all of the events. She helps me with my memory and we exchange comments to refresh each other's memory. From then on until the end of the book, it is really a memoir of the two of us, not just me.