Hi Jill. A quick search of our Bloody Bill Anderson Mystery messages archives revealed only this one Burgess:
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Re: Guerrillas that still need to be researched.

Here are some more for our members to research.

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- Bryson, G.W. (Wash). Bushwhacker.

- Burbridge, Cllnton. guerrilla.

- Burch, ___. Bushwhacker.

- Burgess, W.H. With Quantrill.

- Burkett, ___. Lt. leader of guerrilla band.

- Burkhart, ___. Guerrilla.

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You will find this W.H. Burgess and possibly your relations mentioned in "Branded as Rebels" by Eakin and Hale.
The most comprehensive list of Quantrill's Guerrillas I have found is at:

http://www.kansasheritage.org/research/quantrill.html

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One thing I have learned is that none of the lists, so far, contain anywhere near a complete list of those who served under Quantrill. Frank James is quoted from his own list of guerrillas, that he compiled around the turn of the twentieth century, by several authors but I have been unable to find the list for myself despite repeated efforts to do so on this and other Civil War boards.
~Jay~