Isabel Allende began writing daily letters to her mother when she was a teenager. Over the next several decades, they exchanged over 24,000 of them. Allende credits their letter writing with removing the need for small talk and creating a deep bond between them. Knowing that she had to write to her mother every day pushed her to pay attention to her life in a way that, she says, was central to her becoming a writer.  Letters have been a throughline in her books as well. Allende’s best-selling novel, “The House of the Spirits,” began as a letter to her dying grandfather. “The House of the Spirits” has just been adapted into a new TV series, and the connection between mothers and daughters is central to this multigenerational saga. In this episode of “Modern Love,” Allende tells the host Anna Martin about the transformative power of letter writing on her relationships and career.  Subscribe today at nytimes.com/podcasts (http://nytimes.com/podcasts) or on Apple Podcasts and Spotify. You can also subscribe via your favorite podcast app here https://www.nytimes.com/activate-access/audio?source=podcatcher. For more podcasts and narrated articles, download The New York Times app at nytimes.com/app.