Erasmus Alvey Darwin, nicknamed Eras or Ras, was the older brother of Charles Darwin, born five years earlier. They were brought up at the family home, The Mount House, Shrewsbury, Shropshire, England
Portrait of Erasmus Darwin by Julia Margaret Cameron in 1868.
Susannah Darwin was the wife of Robert Darwin, a wealthy medical doctor, and mother of naturalist Charles Darwin, and part of the Wedgwood pottery family.
Susannah Darwin by Peter Paillou (the Younger), watercolour painted on ivory, 1793.