Simplify the following text for a Grade 10 native English-speaking person.
Original: Diana , Princess of Wales , was descended from two of Charles ' illegitimate sons ; Henry Fitzroy , 1st Duke of Grafton , and Charles Lennox , 1st Duke of Richmond .
Simplified: Diana , Princess of Wales was descended from two of Charles ' illegitimate sons ; Henry Fitzroy , 1st Duke of Grafton and Charles Lennox , 1st Duke of Richmond .