Possibly Lieut. Robert Aldrich of the 6th South Carolina Cavalry.
Aldrich was adjutant of the 6th South Carolina Cavalry and commanded a three company battalion of the dismounted men of Calbraith Butler's brigade (4th, 5th and 6th SC). See CMH SC extended p.429, Seigler Vol.4, p.112, Brooks, Butler and his Cavalry, p.380-381. Seigler states that the 6th (as part of John Dunovant's brigade) may well have been engaged at Reams' Station on the 25th.