What is the author's tone in Telling Secrets by Frederick Buechner?

Frederick Buechner writes his autobiographical work, "Telling Secrets" in a reflective and bittersweet tone. While he certainly was damaged by his mother's unstated though militant legacy to keep secrets about what she deemed taboo, his struggle to free himself from those binds have healed the wounds. He seems to hold no animosity toward his mother—rather, he appears to hold sympathy and understanding.