Ptolemy XV Caesar (/ˈtɒləmi/; Greek: Πτολεμαῖος Ptolemaĩos; 23 June 47 BC – August 30 BC), nicknamed Caesarion (Καισαρίων, "Little Caesar"), was the last pharaoh of Ptolemaic Egypt, reigning with his mother Cleopatra from 2 September 44 BC until her death by 12 August 30 BC, then as sole ruler until his death was ordered by Octavian (who would become the first Roman emperor as Augustus). Caesarion was the eldest son of Cleopatra and the only known biological son of Julius Caesar, after whom he was named. He was the last sovereign member of the Ptolemaic dynasty of Egypt.