Caesarion

Ptolemy XV Philopator Philometor Caesar , better known by the nicknames Caesarion and Ptolemy Caesar , 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,BC, up to August 23,BC, the time his death was ordered by Octavian, who would become the Roman emperor Augustus. It is unknown whether Octavians 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.

Caesarion was born in Egypt on June 23, 47 BC. His mother Cleopatra insisted that he was the son of Julius Caesar. Caesarion was said to have inherited Caesars looks and manner, but Caesar apparently did not officially acknowledge him. Caesars supporter Gaius Oppius wrote a pamphlet which attempted to prove that Caesar could not have fathered Caesarion. Nevertheless, Caesar may have allowed Caesarion to use his name. The matter became contentious when Caesars adopted son Octavian came into conflict with Cleopatra.

Source: Wikipedia