Two children looking over a stone bridge

Two children looking over the stone wall of a bridge at the river under flowing under it. The photographer's shadow can be seen in the bottom right-hand corner. There seems to be a leather strap laid over the wall of the bridge, so I wonder if there is also a dog somewhere, and this is a picture taken during a family walk with the dog?

The taller of the two children has something white in their hand - perhaps a stone to throw in the water?