Simplify the following text for a Grade 8 native English-speaking person.
Original: He has two brothers , the physicist and philosopher Carl Friedrich von WeizsÃ cker and Heinrich von WeizsÃ cker , who was killed in action in 1939 . In 1967 , his sister , Elisabeth married Dr. Konrad Raiser , the former General Secretary of the World Council of Churches ( WCC ) His grandfather Karl von WeizsÃ cker was Prime Minister of the Kingdom of WÃ 1\/4 rttemberg , and was ennobled in 1897 and raised to the hereditary title of Baron ( Freiherr ) in 1916 .
Simplified: His grandfather Carl von WeizsÃ cker had been Minister President of WÃ 1\/4 rttemberg