Patrick Bouvier Kennedy (August 7, 1963 – August 9, 1963) was the youngest child of United States President John F. Kennedy and First Lady Jacqueline Kennedy. His elder siblings were Caroline, John Jr., and Arabella.

Born prematurely, Kennedy lived for just 39 hours before dying from complications of Hyaline membrane disease (HMD), after desperate attempts to save him failed. His infant death left the first family and nation in mourning. However, it also brought HMD (later known as infantile respiratory distress syndrome) into the public consciousness, inspiring further research.

In August 1963, the 34-year-old Jacqueline Kennedy was in her third year as first lady and in the third trimester of her fifth pregnancy. Kennedy had suffered a miscarriage in 1955, followed the next year by a stillborn baby girl whom the Kennedys planned to name Arabella after a ship with that name. Two healthy children followed: Caroline in 1957 and John Jr. in 1960. As John had also been premature, Kennedy asked her obstetrician, John W. Walsh, to accompany her when she and her children spent the summer in Hyannis Port, Massachusetts. The nearby Otis Air Force Base Hospital had also prepared a suite for her in case it was necessary.

On the morning of Wednesday, August 7, Jackie took Caroline and John Jr. for a pony ride in Osterville, Massachusetts. While the children were riding, Kennedy felt labor pains. Walsh was summoned, and they were taken by helicopter to Otis Air Force Base.

President Kennedy was at the White House at the time. August 7 was the 20th anniversary of the day the United States Navy had rescued him in World War II after he had spent five days marooned on an island in the Pacific. Kennedy had been in command of Motor Torpedo Boat PT-109 when it was rammed by a Japanese destroyer, killing two of his crew. His heroics had helped launch his political career. PT-109 and August 7 were never far from his mind, and he kept a scale model of the boat on a shelf in the Oval Office and each day used a metal tie clasp shaped like a torpedo boat, with PT 109 stamped across its bow.

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.

— Thurston Clarke, JFK's Last Hundred Days (2013)

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. The caesarean section was performed by Dr. John W. Walsh, who had also delivered John Jr. in 1960. The infant's birth weight was 4 pounds 10+1⁄2 ounces (2.11 kg). He was the first child born to a serving U.S. President and First Lady since the 19th century (third overall after Esther (1893–1980) and Marion Cleveland (1895–1977) during the second presidency of Grover Cleveland).