Have since learned from the link below that Alvey R. Johnson Jr. (1842-1862), enlisted same day as his brother Benjamin Milam Johnson (1838-1915) at Camp Wigfall, AR in Co. E, 3rd TX Cavalry, and died of a fever at Chesterville (near Tupelo), MS on July 9, 1862.

Also, their father's ward, Mortimor W. Bradley, only son of John M. Bradley of Panola County, TX, of Co. E, 3rd TX Cavalry was taken prisoner at Big Spring, near Corinth, on 2/12/1863

Still have not verified where James Lockert Johnson (12/25/1829-12/31/1862) died, but among the deaths reported include at least one member of Co. D, 3rd TX Cav who was killed on that same day at the Battle of Murfreesboro where was claimed the life of Milam's brother-in-law, Silvaman Texas Hilliard of Co F, 10th TX Cavalry.