YOU SAID:

I had a brother at Khe Sahn Fighting off the Viet Cong They're still there, he's all gone

INTO JAPANESE

ケサンそういうベトコンを戦う弟を持っていた彼らはまだそこにいる、彼はすべて行ってしまった

BACK INTO ENGLISH

They had a younger brother fight the Viet Cong that they're still there, he's all gone