YOU SAID:

i slept with my sister only after my parents died but I think my grandpa will tell them in heaven

INTO JAPANESE

両親が亡くなってから姉と寝ました

BACK INTO ENGLISH

I slept with my sister after my parents died

INTO JAPANESE

両親が亡くなった後、私は姉と眠りました

BACK INTO ENGLISH

I slept with my sister after my parents died