I know this post is dated from 2001 but I have some new information based on what you posted. You may already have discovered this. Here is what I found out:
Rasberry and RoseBerry Byrd are two different people and two different genders. If you look at the census record from 1860 & 1870 it lists Rasberry as male 1 yr old and 11 yr old. Roseberry married Asa J Huffman. Roseberry is female.
I believe Jacob, William & Thomas Byrd are all related if not brothers. Possibly sons of Alexander Byrd from Brunswick County.
Very interested in what happened to Thomas Byrd after 1860 which shows him with his wife Susan and son - Charles Byrd. Charles was the father of Joseph Jackson Byrd (my Grandfather). After 1860 Thomas & Susan disappear.
If you or anyone reading this has information on Thomas Byrd or a Thomas Rasberry Byrd - linking them to Alexander Byrd or Bird. I'd love for you to contact me.