Kathleen Pryor was mentioned in the biography of Syd Chaplin, Charlie’s half brother written by Lisa K Stein. It was noted that she had studio records going back to 1918. She may not have been working there at that time because she would have been 12 years old in 1918.
1930 Census, Los Angeles, CA – Recorded living on 1211 N Ogden Dr. Her occupation was listed as secretary at movie studio.
Surprisingly I found Ms. Pryor on The Swedish Film Institute website where she was recorded as the Production Secretary for The Great Dictator (1940) and Limelight (1952), both Chaplin films. It looks like she continued to work in the film industry and with Chaplin long after the 1925 photo above.
January 12, 1987 Death Record in Los Angeles, CA for a Kathleen Ruth Pryor, born in IL in 1906. Her mother’s maiden name was Luby. There’s a 1906 birth record in Cook County, IL for a Kathleen PRIOR born to Thomas Prior and Kitty Laby.