Regarding this photo:
28828510_121807915137.jpg
Interested, I agree with you. I have thought for a long time that Sarah and Abby greatly resembled each other. However, I did a bit of research and found that this photo was added to the find-a-grave web page for Sarah Anthony Morse Borden, by Frances Earp Meyer. If you go into the photos section, and click on the photo, you will find the following information (Underlining is mine.):
Sarah Anthony Morse was the first wife of Andrew Jackson Borden and the mother of Emma Lenora, Alice Esther, and Lizzie Andrew.
I would say this was taken at the time of her marriage.
Source:
http://tinyurl.com/y76gew2z
Source: Sarah Anthony Morse Borden:
http://tinyurl.com/y6w75qh2
I recall that we had a forum discussion regarding the portraits of Andrew and Sarah Borden that were taken when they were young. So, I did a forum search and found the thread I remembered.

A huge THANKS goes to mbhenty, for the information and pictures he provided us with in the thread titled,
Lizzie Borden Gothic Ballad. See if you don’t agree that the picture above was cropped from the portrait of Sarah Borden when she was young:
http://tinyurl.com/yaxkjvgv
MB, you stated in the above thread that Stefani was the one who discovered the portrait of Andrew. Did she also discover the portrait of Abby? What is the name of the museum where the portraits were found, and how did they obtain them?
Frances Earp Meyer also added this photo (1 of the 3) of Sarah with baby Emma Lenora, to the find-a-grave web page for Sarah Anthony Morse Borden:
28828510_121807936649.jpg
Here is the statement she wrote regarding that photo (Underlining is mine.):
Sarah Morse Borden with eldest daughter, Emma Lenora. Taken about 1853 in Fall River, Massachusetts.
Source:
http://tinyurl.com/ybw3q7a6
It’s unfortunate that the date was cut off; you can barely see it at the bottom of the photo. However, I agree that Emma appears to be about 2 years old in that photo. If the 1853 date is correct, then Sarah would be at least 7 years older than when she had her picture taken for the portrait.
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