תרגום - אנגלית-יפנית - I'll fight for you, I'll die for you, I'll live...

I assume Kayleigh was pronounced "Kay-lee". If it's pronounced "Kelly," then the Japanese is
ケリーちゃん、俺は君のために戦う、君のために死ぬ、君のために生きる。君のためなら何でもする
I had to put the "Kayleigh" at the beginning of the statement, to sound natural in Japanese.