"Rule Breakers" In The Family?

Violet and Cecile White

I found this photograph of my grandmother Cecile White Howard (1917-1983) and her sister Violet White Hicks (1920-2005).    The sign in the middle says "DANGER  KEEP OFF". I don't know the story behind the picture, but it would appear we have a couple of daring rule breakers in the family!  I wonder of Grandmother White (Stella Holyfield White) knew.

If any White family cousins know the story behind this photograph, I would love to hear  (and share) it.