Dear Robert,
Here are some possibilities, in relation to a Garfield Anderson.
"United States Census, 1930", database with images, FamilySearch(https://familysearch.org/ark:/61903/1:1:XKJR-HD4 : 8 December 2015), Garfield Anderson in entry for John Alderman, 1930.
[Edna as a DAUGHTER of Garfield instead of a SISTER.]
"United States Census, 1930", database with images, FamilySearch(https://familysearch.org/ark:/61903/1:1:X4PG-W62 : 8 December 2015), Garfield Anderson in entry for Lily L Anderson, 1930.
[Everyone born in England.]
Can you locate Edna in the 1940 US census? It should say where she was born.... Hope this helps. -NGP