I have FOX and FANNING families in my Isabella / Gratiot Co tree: DAVIS O'BRIEN Jun08. Feel free to search it.
Have you looked as the Isabella Co vital records that are available online? http://www.mifamilyhistory.org/isabella/
There is a search feature on their first page for you to enter your surnames, it is very helpful.
Good luck, Karen SowardsFam@aol.com