I don't know how much information you already have, but if I have the right person in Erath County, Texas, it looks like Sarah's husband was Benjamin W. Head. Sarah died in 1884, then Benjamin remarried. Eldora "Dora" had a twin sister Norah. You can find lots of information on the family at
www.familysearch.org. Try to search on Benjamin W. Head, with no other information at first. Also, if you have not been to the Erath County genweb site, there is a query from someone looking for the same family.
http://www.rootsweb.ancestry.com/~txerath/Finally, I would suggest posting a query on the Erath County message board (depending on whether I have the right family)!
I am not related, just trying to be helpful.