"I need to get me that letter from the Army."

"You can use the library here to write out that letter."

"What was the name of the girl who wrote that letter?"

I had that letter four months ago, but nothing since.

Or it used to be until I got that letter.

Almost immediately after I got that letter, he was killed.

It then remains that letter for the rest of the game.

What must have been his feelings when he read that letter?

"You think he's the one who wrote that letter to her?"

In this case you'll have three months from the date you received that letter.