Very interesting to me. My 3x g-grandmother, Nancy Fox, a "free mulatto" was born around 1830 in Caroline, too. Because Fox was her maiden name and the pre-1850 censuses don't list out family members, I have had a hard time tracking down any info that might lead me in the right direction as to who her Fox family was (other than census info indicating the Fox families that lived near her and her children).
As far as photographs: Do you know what church the family attended? I see that there are a few marriage licenses for Lucy's siblings. Perhaps you could check those, find out what (if any) church/pastor officiated, and see if there are any church photographs of the family? I know that many churches did centennial programs, which typically contain photographs of the founding families.
My Fox-Taylor descendants attended Jericho, Mt. Carmel, and Oxford Mt. Zion, fwiw.