I purchased in Lake Co., CA, the subject undated studio portrait of a young girl identified on the back of the mount:
"Viola Knowles. Bell Kemp daughter"
This individual appears in Public Member Trees posted on ancestry.com. She is listed in the 1910 Census data for Santa Rosa, Sonoma Co., CA; the 1920 Census data for Santa Rosa (resided at 822 Monroe Street), Sonoma Co., CA; and the 1930 Census data for Santa Rosa (resided at 410 3rd Street), Sonoma Co., CA.
Viola May Knowles, born 22 May 1907 in Sonoma Co., CA, died 17 Dec 1965 in Mendocino Co., CA, was the daughter of William Henry Knowles (1886-1917) and Belva Olretta Butts (1889-1964) (she also married William Kemp).Viola married Earl W. Robbins (1906-).