Simplify the following text for a Grade 7 native English-speaking person.
Original: Polonius is Claudius ' trusted chief counsellor ; Polonius 's son , Laertes , is returning to France , and Polonius 's daughter , Ophelia , is courted by Hamlet .
Simplified: Ophelia is Polonius ` daughter . After her father , Polonius , is killed by Hamlet she goes mad .