This picture we have seen before - Dad and Sally. Dad must be about two, which would make Sally seven years old. The caption on the back reads:

These are Annie Mudd Simmons & Henry C. Simmons Children.

First Miss Sarah Simmons

Second Mr Roy Simmons

Niece & Nephew

  of Mrs Margaret Mudd,

& Asa S, Calkin

Margaret Mudd Calkin was Annie Mudd's half sister.