Walter Gulch is a deleted character concept that was discussed in early drafts of The Wizard of Oz (1939) who would have been the son of Miss Gulch. Therefore, he was envisioned to have a counterpart named Bulbo as the Wicked Witch of the West's son who she wanted to put onto the throne of Oz.
It is unclear how far the character made it into development, but he does appear in some early scripts such as at least one written by Noel Langley as noted by a Smithsonian Magazine article written by Maguire coincidentally. This script dated May 4th, 1938 was lost in the MGM vault until 1987 when it was donated to the National Museum of American History. Unfortunately, only but one page is available to the public so the exact context Langley wrote is unknown.