Thank you for the various thoughts.
I certainly wasn't casting any criticism!
As I said, I'll have to do some more investigating. Possibly my great grandfather's family took a trip to Brighton - they don't appear to have been struggling money-wise, but would they have gone there from Blackburn as opposed to Blackpool for what I presume is a seaside holiday? Maybe there's a girl cousin to one of my great grandparents lurking around who I haven't discovered yet?
Cathryn