Difficult to find her in earlier years. Following are possibilities:
Viola Stephens
Florida, Marriages, 1830-1993, marriage: 29 Jul 1928 Florida
spouse: John P Porter
https://familysearch.org/pal:/MM9.1.1/VRCR-GVD
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Viola Porter, b. 1890, 45 yrs. Georgia, Res: Bay, Florida, State Census, 1935
https://familysearch.org/pal:/MM9.1.1/MNJF-VT2
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1940 Bay County, Florida Census, Precinct 3
23
Levi Gaff, Head, male white, 30, wd, b. Alabama
Francis Gaff, Dau., fem. white, 3, b. Florida
Viola Porter, Mother, fem. white, 50, wd, b. Georgia
[Data from Heritage Quest census records, but also listed on family search]
https://familysearch.org/pal:/MM9.1.1/VTH3-LX6