Thank you, Anne.

I didn't know which units he served in, let alone that he had been a secretary to Stonewall Jackson.

Thanks to the knowledgeable and helpful people on this msb, I have learned much more than I expected. I received a direct email from one member who informed me that Dewitt Gallagher's Civil War diary is online and contains several references to Hugh McGuire. For example:

"...Hugh McGuire was captain of Co. E {11 VA Cavalry). He married my sister Sallie, January 12, and was killed on Lee's retreat, dying at Amelia Springs, Virginia. No braver trooper ever lived!"

The entry for January 12, 1865 provides quite a few details on their wedding which was attended by a number of prominent Confederates, including Gen. Fitzhugh Lee "standing with Betty Payne", and of course Dr. Hunter McGuire,standing with Evelyn Withrow. "We dance until 2:30 a.m."

I don't know whatever happened to Sallie Gallagher McGuire, or whether any children were born from their three-month marriage.
Thanks again, Mac