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?
Lynda Bird Johnson Robb:  She is the oldest living child of a U.S. President following the death of John Eisenhower on December 21, 2013. John Eisenhower: John Sheldon Doud Eisenhower (August 3, 1922 – December 21, 2013) was a United States Army officer and military historian.
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