Hi Laura, I'm posting this online rather than sending to your email so that others searching this forum can see the info as well.
I found Earl Wills Gregory in the US Censuses as follows: 1900 with his parents Samuel and Grace (Wills) Gregory in Delamar, Owyhee, Idaho along with siblings Raymond, Beatrice, Florence, and Ruby. 1920 at Fort Bliss, El Paso, TX as a sergeant in the US Army 1930 in Oswego, Kendall County, IL with wife Helen and daughters Grace, Betty, Lois and Dora Mae 1940 in Oswego, IL with daughter Lois
His WW II draft card gives his name as Earl Wills Gregory, birthdate October 4, 1890, birthplace Granite, Montana.
Public member trees at Ancestry.com give his mother's maiden name as Grace Wills. Findagrave has memorials for his parents Samuel and Grace Gregory both buried Roosevelt Memorial Gardens, Los Angeles County, California. Samuel was born 1865 and died 1936, Grace was born 1864 died 1933.