I agree, Linda. Cooper referring to him at "Mr." seems to suggest he was a civilian, perhaps acting as aide de camp. I have searched Confederate service records trying to locate any variation I could think of for Blackstone/Blackston/Blacksten and first name Pleasant or Napoleon or Nip and can't find him. On his Dawes Application Packet he says he has lived in the Cherokee Nation his entire life.

But your real question was about Louisa who died at Wheelock. I'll see if I can find anything but I'm guessing you've already looked everywhere I can think to look. You might try the Indian-Pioneer Papers. I don't know how much of them is online. NSU Library has the index on microfilm in their special collections.

I would very much like to read the letter to Louisa, if you don't mind, in whatever format is convenient.

You can email me at martikw@history-sites.com.