YOU SAID:
Luigi is Mario's wife's brother's sister's husband's brother.
INTO JAPANESE
ルイージはマリオの妻の妹の夫の兄弟です。
BACK INTO ENGLISH
Luigi is the brother of Mario's wife's sister's husband.
INTO JAPANESE
ルイージはマリオの妻の妹の夫の兄弟です。
BACK INTO ENGLISH
Luigi is the brother of Mario's wife's sister's husband.
That didn't even make that much sense in English.