I think this photo has a real signature but no gaurantees.
This wonderful photo has been folded at some stage. See the photos.
The photo size is 197mm/ 250mm
Marion Cecilia Davies was an American film actress, producer, screenwriter, and philanthropist. Davies appeared in several Broadway musicals and one film, Runaway Romany and then became the mistress of newspaper tycoon William Randolph Hearst. He then took over management of her career. Wikipedia