Thank you RCJ! With the first names of all the children in the 1870 census, I'm pretty certain that this is her. But none of the names had any other links, so I'm still searching for more info. I have seen this 1880 census, but I'm not convinced it is her, so I'm still searching that connection. Is she a member of your family? She is the one that has baffled me for years.
Thanks again!