We have found a Mary Holton. age 63, in St. Louis, MI, in the 1920 census. She is living with her husband, Joseph E. Holton, age 76. She has her niece, Vera Damon, age 15, daughter of Joe Daman, living with her. We suspect Mary Holton's maiden name is Daman. Might this be the Mary Daman you're seeking?