Born prematurely, Kennedy lived for just 39 hours and 12 minutes before dying from complications of hyaline membrane disease (HMD), after desperate attempts to save him failed.

It brought HMD (later called infantile respiratory distress syndrome) into the public consciousness, inspiring further research.

[2] All of which may explain why Kennedy's friend and fellow World War II naval veteran Ben Bradlee is certain that when the president's secretary, Evelyn Lincoln, hurried into the Oval Office at 11:43 a.m. on August 7, a Wednesday, to report that Jackie had gone into premature labor on Cape Cod, there was "no way in God's earth" that he did not think, My child is being born 20 years to the day when I was rescued, a coincidence providing an additional emotional dimension to a day that would be among the most traumatic of his life.While his father was aboard Air Force One, the infant Kennedy was born by emergency caesarean section at 12:52 p.m. on August 7, 1963, at the Otis Air Force Base Hospital in Bourne, Massachusetts, five and a half weeks prematurely.

[1][6] Shortly after birth, Kennedy developed symptoms of hyaline membrane disease (HMD), now called infant respiratory distress syndrome (IRDS).

Five hours after birth, the infant, accompanied by Dr. Drorbaught, was rushed by ambulance to Boston Children's Hospital, 70 miles (110 km) away, in under 90 minutes.

The president, who had reportedly slept only four hours since the birth, was photographed arriving at Otis Air Force Base looking "grave and appearing tired.

The president's mother, Rose Kennedy, was in Paris and was told not to return for the funeral, but the first lady's sister Lee Radziwill had already flown in from Greece before the baby died.

His body and that of his stillborn sister Arabella were reinterred on December 5, 1963, alongside their father, at Arlington National Cemetery and later moved to their permanent graves in Section 45, Grid U-35.

[14] According to Dr. Suhas M. Nafday, director of Newborn Services at the Children's Hospital at Montefiore Medical Center in New York, the child's death "energized the neonatal researchers into action to look for an effective management of respiratory distress syndrome.

"[15] In a review of advances in clinical medicine, researcher Thor Hansen observed that the "medical profession did not have the tools to help" Kennedy, "the newborn son of arguably the most powerful man in the world," but 50 years later, treatment of his condition would be considered routine, with survival expected.

Secret Service agent Clint Hill recalled the couple having "a distinctly closer relationship" that was visible after the child's death.

Press Secretary Pierre Salinger believed that the couple had been brought closer by the presidency but even more so by the child's death.