The hoop skit is the give-a-away. They were out of style by the early 1870s when "Molly" was born. Thanks for the correction. Also where does the "Molly Pinn" name you've assigned to her come from? I've never seen it in any records associated with this individual. In most sources she is referred to as either Margaret or Mary. Ditto for Alethea Preston "Pinn." In most records she's either Preston or Colvin.
Morning Alex! I had not really been on this site in some years. It was not EASY changing that picture, I kept getting these annoying pop-ups. You were not the 1st to realize that that dress was way past Molly's age. I think her name was Margaret, but I will check. Will send you an email on the rest.