Why do Muslims and Jews call Abraham call father of all prophets?

God changed Abraham's name from Abram to Abraham (in Genesis 17:5), to show that Abraham was to be the "father of many nations". The Hebrew for this name is a direct translation of that phrase. In addition, he was the first of the forefathers for the Jewish religion, as the father of Isaac and the grandfather of Jacob. Each of them is entitled to the title Father. At Passover, there is a Jewish song that calls these men the 3 Fathers. Their wives are known as the 4 Mothers.

Answer:We (Jews) call him "Abraham our father" (Avraham avinu), not "Father Abraham." We call him "Avraham avinu" whenever we refer to him in conversation, not just on one occasion.