Some of the census listings record her birthplace as Louisiana, while others show Mississippi.
The censuses don't often list the relation of members of the Biddle household, so it isn't always clear which members are the children of Hosea and Mary.
Much attention has been paid towards one member of the Biddle household" Elenora/ Ellen Nora Biddle, whose death record lists her parents as "T. O. Biddle and Polly Duck". I think the T.O. might be a mistranscription of a capital H, which can look like the two letters, and certainly does in one of the census listings. Polly is a nickname for Mary (according to Wikipedia), so this Mary's last name may very well be Duck.
I will try to get a copy of the actual record to try and confirm this hypothesis.
If this is the case, then we can speculate that she was perhaps a member of the Duck family, perhaps those who lived around Amite?
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