Tabb, Robert M., enlisted April 21, 1861; promoted sergeant 1863; sergeant-major 21st Va. Regt. Sept., 1864; killed at Cedar Creek, Oct. 19, 1864. pp. 314/5
Our loss was heavy, and among the killed was that splendid soldier, Maj. Gen. Ramsuer!

Cedar Creek - F Company lost Sergeant R. M. Tabb, killed; Corporal W. C. Tyree and L. M. Couch, wounded. That gallant young officer, Lieut. M. L. Hudgins, had command of a line of skirmishers and was shot through both legs, but succeeded in bringing off his command, and took to the mountains! p.276

One of Jackson's Foot Cavalry
his Experience and what he saw During the War 1861-1865,
Including a History of "F Company," Richmond, Va.,
21st Regiment Virginia Infantry, Second Brigade,
Jackson's Division, Second Corps, A. N. Va.:
Electronic Edition. Worsham, John H.
http://docsouth.unc.edu/fpn/worsham/worsham.html

.....

Tabb, Robert M., enlisted April 21, 1861 age 30;[ wounded on 23 March 1862 at Kernstown, VA (Sprained ankle); detailed on 15 November 1862 (Detailed, clerk to General Taliaferro); returned on 15 January 1863 (Estimated day); promoted to Full Corporal on 30 April 1863]; promoted sergeant [15 May (Estimated day)]1863; sergeant-major 21st Va. Regt. Sept., 1864; killed at Cedar Creek, Oct. 19, 1864.
http://21vafco.org/roster.htm