“Dear Lottie and Herbie, by the time you read this, I will be dead . . . That's why I'm writing this letter. I've had a long and happy life doing what I loved best . . . Now it's time to make room for someone else on this earth.” 

The letters Petra and Michael sent out echo the words of a letter in a children’s book Petra wrote 10 years earlier: the final installment in her beloved series about Lottie the chicken. But it was their relationship – not their work – that Petra and Michael seemed to think of as their most important artistic achievement. Were their deaths, and these letters, their final creative collaboration?