I had those conversations with my uncle, who was wounded in Muse-Argonne. You will never understand how important that last night's talk was. I did not have it with my uncle, and with my Dad it was not possible, as he was left mute by a stroke. I envy your opportunity.
Write it down, and share it with your state archives.
I wish I would have been a better record keeper 20 years ago. My Paternal Great Grandmother was born in 1892, and died in 2007. She was really sharp up until the last few years. The stories she told about her first horse and buggy, the boys heading off to the war(WWI), getting a telephone in the house...............