 In 2003, when Grogan's dog, Marley, died at age thirteen, Grogan wrote a column in "The Philadelphia Inquirer" honoring him, and he received over 800 responses from his readers.The readers' astounding response and interest in Marley sparked Grogan's decision to write a book, due to the realization that he had "a bigger story to tell" and "owed it to Marley to tell the rest of the story.