Question: Lynda Bird Johnson Robb is the oldest living child of a U.S. President following the death of a United States Army officer who served as the United States Ambassador to where?
{'answer': 'Belgium', 'supporting_facts': [['Lynda Bird Johnson Robb', 0], ['Lynda Bird Johnson Robb', 2], ['John Eisenhower', 0], ['John Eisenhower', 2]]}