No real idea of the date. The relative, who is a cousin once removed, and her husband actually managed the City Varieties in Leeds from about the 1930s to late 1950s. Previously they lived in Scarborough, siblings performed in the Moss Empire, based at the Alhambra in Bradford, and their father apparently once owned (or more likely managed) the Tyne THeatre in Newcastle. Hence the four locations I mentioned.
Others more knolwledgeable on clotihng styles might be able to date the photo, but I would say 1920s or 30s, wouldn't you?
OK dates from the late 19thC, doesn't it?
Tim