YOU SAID:

I am my own grandfather, also I married my sister's son

INTO JAPANESE

私は実の祖父であり、妹の息子と結婚しました

BACK INTO ENGLISH

I am my biological grandfather and married my sister's son

INTO JAPANESE

私は実の祖父で、妹の息子と結婚しました

BACK INTO ENGLISH

I am my biological grandfather and I married my sister's son

INTO JAPANESE

私は実の祖父で、妹の息子と結婚しました

BACK INTO ENGLISH

I am my biological grandfather and I married my sister's son