I was researching Mary Devereux b 1804 some years back trying to find information on William St. John Elliott a slaveholder in Adams Co., MS and came across information on Louisiana Devereux.

Was Louisiana Devereux the sister of Julien Sidney Devereux?

Below are links to articles on the web which might be of help:

The Henderson Democrat
Sat., Nov. 29, 1856
Notice: The undersigned, having at the May term of 1856 of the County Ct...Rusk...obtained letters of Test. upon the estate of Julien Sidney Devereux...Sarah Devereux, Executrix, John Landrum, Executor.
Source:
http://www.ladytexian.com/TXRusk/news/news1850.htm

Here is an interesting article:
http://www.hendersondailynews.com/articles/2007/11/09/news/01montefri.txt

Let me know if this helps.

Ed Adams