He Was 3
Cleopatra wsas 22 years old when she had her first son.
Cleopatra was 18 years old when she had her first child, Caesarion, with Julius Caesar.
For all practical purposes, Cleopatra's death ended the rule of the ancient kings and queens. Octavian/Rome took over Egypt. But the situation gets a little tacky as far as precision is concerned. Cleopatra had made her son, Ptolemy XV (Caesarion) her co-ruler according to law. This was okay during his childhood, but at the time of Cleo's death, Caesarion was a grown man and was actually the king of Egypt. He outlived her, so for a brief time he was the Egyptian ruler. (Just a brief note: Caesarion was 17 years old at the time, but in the ancient world he would have been considered an adult).
He died in 44 BC and she died in 30BC so obviously he was dead when she died.
Cleopatra's child, Caesarion, was not known to have died in infancy; he lived until he was about 17 years old. After Cleopatra's death in 30 BCE, Caesarion was captured and killed by Octavian's forces. Cleopatra also had three other children, whom she had with Mark Antony, and they survived infancy.
Caesarion, the son Cleopatra claimed was fathered by Julius Caesar, was 17 when he died. He was a grown man by ancient standards.
Cleopatra first took the throne at age 18 (some sources say 17) when her father died, and she took the throne with her younger brother Ptolemy XIII, who was just ten years old at the time. Ptolemy XIII's guardians forced Cleopatra out, so she sought alliance with Julius Caesar. Julius Caesar and his army defeated Ptolemy XIII, and Caesar restored Cleopatra to the throne at age 22, alongside the youngest of her brothers, Ptolemy XIV. This was in 47 BC. A year later, evidently charming Julius Caesar, Cleopatra gave birth to his son, cementing the alliance between Egypt and Rome. Sources vary, with some stating Cleopatra stayed in Rome and other stating she made several visit to Rome. Either way, after Caesar was assassinated, Cleopatra arranged for Ptolemy XIV to be poisoned. She then took the throne, establishing herself as co-ruler with her infant son. She was 25.
Cleopatra was eighteen when she inherited the throne. She was twenty-two when her actual rule began.
She was 17.
Cleopatra was 22 years old when she became the permanent ruler of Egypt. Julius Caesar established her on the throne along with her younger brother.
25years old
Mary, Queen of Scots was only 6 days old when she took over the throne of Scotland. She inherited the throne on December 14, 1542.