The William G. Haydon Papers contains photocopies of family correspondence, short stories, business documents and newspaper clippings: Family correspondence includes William Haydon's letters to his son Bill, March 1919 to August 1926; letters to William Haydon from his son Bill, October 1911 to March 1926; III. Letters from William Haydon to his family March 1919 to January 1926; and correspondence between the four Haydon brothers: William, Curtis, Condit, and Ned, February 1922 to May 1934.

All the letters show a close and supportive family. The personal correspondence between William Haydon and his son Bill reveals a deep affection between the two men.

In May 2001, the Constance Modrall Papers, formerly MSS 372 SC, were added to this collection. They comprise folder 10 of this collection.