Let me hasten to correct one item about your ancestor. Although he and his regiment absorbed the heaviest attacks on Confederate lines at Kennesaw Mountain, Vanlandingham wasn't captured there. He was captured in one of the last battles east of the Mississippi River, West Point GA, April 16, 1865. Fort Tyler, named for the Confederate leader who died defending the fort, actually stood on Alabama soil just west of the Georgia line.

http://www.forttyler.com/index.htm
http://www.exploresouthernhistory.com/forttyler2.html
http://www.historynet.com/robert-charles-tyler-last-american-civil-war-confederate-general-slain-in-combat.htm

Here's a link to the regimental history --
http://mississippiscv.org/MS_Units/35th_MS_Inf.htm

Graves of General Tyler and Captain Gonzales, killed Apr. 16, 1865