John Gardner Coolidge died in 1936.
John Fentress Gardner died in 1998.
John Reynolds Gardiner died on March 4, 2006, in Anaheim, California, USA of pancreatitis.
John Gardner was born on July 21, 1933.
John Gardner Murray was born in 1857.
John Coolidge Adams was born on February 15, 1947.
John Gardner Coolidge was born in 1863.
John Fentress Gardner died in 1998.
John Dunn Gardner died in 1903.
John Twiname Gardner died in 1914.
John Gardner - composer - died in 2011.
John Lane Gardner died in 1869.
John Gardner Wilkinson died in 1875.
John J. Gardner died on 1921-02-07.
Philip John Gardner died on 2003-02-14.
John Gardner - American writer - died on 1982-09-14.
John Lowell Gardner II died on 1898-12-10.
I think you may have confused John Coolidge with someone else. John was the oldest son of president Calvin Coolidge (and his wife Grace). John married Florence Trumbull in 1929; their first daughter (Cynthia) was born the next year, but she did not die young-- she died in 1989. And their other daughter, Lydia, did not die young either-- in 2000, when John died at age 93, she was still alive.