I don't know if this line could be part of your Brandon line, but I am willing to bet it is. From what I have been able to find, this line began with Gerard Brandon (1750-1823) who emigrated here from Ireland. All - or at least most Brandons - seem to originate from him.
With this in mind, I am willing to bet a branch off of that Irishman is from your family. My research into the Brandon family, which concentrates on the Brandons that lived in Adams County, MS in the mid-1800s, may be of some help to you...
http://thebrandonchildren.com/
I hope that the early research of the Brandon family I have done may aid you in your own efforts. Best of luck!