That's quite a resume your father in law has got. He's a grandson of a Confederate soldier? What regiment was he in and what campaigns did he serve in?
I'm reading about Fremantle's diary at the moment. He was a British visitor and was at Gettysburg. He talked about the famed rebel yell.
He said if there was an explosion among the Federals, a Confederate yell would immediately follow. The Southern troops, when charging or to express their delight, always yell in a manner peculiar to themslves. The Confederate officers that the rebel yell has a particular merit, and always produces a salutary and useful effect on their adversaries. A corps is often spoken of as a "good yelling regiment."
Rob