Fatimah bint Amr (Arabic: فاطمة بنت عمر) (died 576) was Muhammad's grandmother. She was married to Abd al-Muttalib ibn Hashim. Her full name was: Fatimah daughter of `Amr ibn `A'idh ibn `Imran ibn Makhzum. Her mother's name was Sahre, Sahre's mother was Tahmur. Tahmur was the daughter of Ubeyd, the son of Qusai.
I have never heard of the Prophet's (P.B.you.H) NANA so we don't know what his name is
Grandfather name what?
While we do know tha names of the grandfathers, the names of the grandmothers were not considered of importance, so are unrecorded.