Ptolemy XV Philopator Philometor Caesar (, Ptolemaios IE' Philopator Philometor Kaisar; ; June 23, 47 BC – August 23, 30 BC), better known by the nicknames Caesarion (; , Kaisarion, literally "little Caesar"; ) and Ptolemy Caesar (; , Ptolemaios Kaisar; ), was the last king of the Ptolemaic dynasty of Egypt, who reigned jointly with his mother Cleopatra VII of Egypt, from September 2, 44 BC. He held the position of sole ruler between the death of Cleopatra, on August 12, 30 BC, up to August 23, 30 BC, the time his death was ordered by Octavian, who would become the Roman emperor Augustus. It is unknown whether Octavian's order was carried out successfully. He was the eldest son of Cleopatra VII, and possibly the only son of Julius Caesar, after whom he was named.