YOU SAID:

when he said that his son died week before,

INTO JAPANESE

彼の息子が一週間前に亡くなったと彼が言ったとき、

BACK INTO ENGLISH

When he said his son died a week ago

INTO JAPANESE

彼が息子が一週間前に死んだと言ったとき

BACK INTO ENGLISH

When he said his son died a week ago