Simplify the following text for a Grade 9 native English-speaking person.
Original: The sole reign of Cleopatra was finally ended by a cabal of courtiers , led by the eunuch Pothinus , removing Cleopatra from power and making Ptolemy sole ruler in circa 48 BC ( or possibly earlier , as a decree exists from 51 BC with Ptolemy 's name alone ) .
Simplified: The reign of Cleopatra was ended by a cabal of courtiers , led by the eunuch Pothinus . They removed Cleopatra from power , and made Ptolemy sole ruler , in about 51 to 48 BC .