Kate and Clara Key (and grandparents?)

There are two little girls in their Sunday best dresses, socks or hose, and shoes. They may be between 5 and 8 years old, but I am not good at guessing ages. The older one has a big bow in her hair. The man has a full head of hair and a full beard both very white. He is wearing a suit and carrying a cane. The woman looks like she also has snowy white hair and in need of dentures. Written on the back is "Kate and Clara Key". There is no date and no mention of a place. There is a second photo of the same children by themselves.

Do you recognize Kate and Clara Key? How about the older couple behind them? They are unknown to me.