Have you tried the Mercer Co., MO web site at
http://www.rootsweb.com/~momercer/index.html for information on your Franklins? There is a search engine where you can type the name you are researching and it will return any mention of that name on the web site whether in a cemetery survey, query, etc. There seems to be several mentions of that surname and perhaps you can determine if it is your line.
I was intrigued by your post because my ancestor John B. Howard also came from Mercer Co. to Douglas Co. He married a Rebecca Jane Barnes, but I don't know if she was also from Mercer or from Douglas. If those names ring any bells, I would surely appreciate knowing about it.
Thanks and Good luck!