Based on age, it is possible that Nancy Wells was counted as a free white female, age 10 to 15, in the household of William Wells on the 1830 Census at St. Helena Parish, LA. (Age bracket isn't correct, but this is the most likely place she would have been.)2
[S356] Jim Perrin. E-mail message.
[S412] 1830 U.S. Census. LA. St. Helena Parish. population schedule.