YOU SAID:

The mother of the husband of the sister of my mother has a brother who has a son who has a wife who's brother is my father

INTO JAPANESE

私の母の妹の夫の母には弟がいて、その息子には妻がいて、その弟が私の父親です

BACK INTO ENGLISH

My mother's sister's husband's mother has a younger brother, and that son has a wife, and that younger brother is my father.

INTO JAPANESE

私の母の妹の夫の母には弟がいて、その息子には妻がいて、その弟が私の父です。

BACK INTO ENGLISH

My mother's sister's husband's mother has a younger brother, and that son has a wife, and that younger brother is my father.