Hi! Wow you posted this quite a long time ago but maybe you will still get this reply! Maybe we are related.
My family has an old Bible (made in 1872) with these names in it. My mother was Margaret Elizabeth Potter before she married my Dad (Huffman). Her parents were Roy Austin Potter and Florence Place.
Roy Potter's parents were Francis (Frank) M. Potter and Sarah Elizabeth Bush (Potter). They traveled from Missouri to Oregon in a covered wagon while Sarah was pregnant with Roy.
We have a marriage certificate (sort of) for Francis M. Potter to Sarah Elizabeth Bush. They were married May 13, 1879 in Bird Island, Minnesota. Isaac Potter and Margaret Southard Potter are not in the book but I think we have record of them elsewhere.
According to my mom, John Bush was Sarah Elizabeth Bush Lincoln's (Abraham Lincoln's step mother's) brother.
And I am Sarah Elizabeth Huffman :)
Geez I hope you get this!!