Do you have anything that states that James Monroe Reese was in the 13th Texas Cavalry? I don't find him listed as being in the 13th, but I did find this listing.
James Reese (First_Last)
Regiment Name 11 (Spaight's) Batt'n Texas Vols.
Soldier's Rank_In Private
Soldier's Rank_Out Private
Film Number M227 roll 30
CONFEDERATE TEXAS TROOPS
11th Battalion, Texas Volunteers (Cavalry and Infantry) (Spaight's)
11th (Spaight's) Cavalry and Infantry Battalion, formerly the 6th Texas Infantry Battalion, was a mixed command organized with 400 men in April, 1862. The unit served in the Department of Texas, then was assigned to Hebert's Brigade in the Trans-Mississippi Department. During the spring of 1864 it merged into the 21st Texas Infantry Regiment. Lieutenant Colonel Ashley W. Spaight and Major J.S. Irvine were its officers.
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Gary D. Bray