Simplify the following text for a Grade 6 native English-speaking person.
Original: Both of Keynes 's parents outlived him : father John Neville Keynes ( 1852 â `` 1949 ) by three years , and mother Florence Ada Keynes ( 1861 â `` 1958 ) by 12 years .
Simplified: Keynes ' father , John Neville Keynes ( 1852 â `` 1949 ) outlived his son by three years .