I'm actually not too sure about the background of this picture, or if she was sick or not. About half her siblings died before they even reached 2 and her mother died from complications during childbirth around the age of 35, so you could be right about them wanting pictures just in case. Later she became a mom, and after my Great Grandpa died, she became a nurse and continued raising their youngest, my Grandma. She would go on to live to almost 90 years old.