The Kennedy home in Brookline, Massachusetts, was the setting for an ordered, disciplined, Catholic upbringing. Rose kept charts on the wall tracking each child’s health, dental appointments, and vaccinations. Joe set competitive standards for his children at the dinner table. The expectation, implicit and explicit, was that Kennedy children achieved things. They won races, brought home high grades, and made the family proud.
Into this household on September 13, 1918, came Rosemary. The birth itself was difficult, and the difficulty may have mattered enormously, though the medical record on this point is not as clear as some secondary accounts suggest.
The family’s physician was delayed. The Spanish influenza pandemic was sweeping the country, and the doctor had other patients to attend to. The nurse present reportedly held the partly-delivered baby’s head in the birth canal for approximately two hours until the physician arrived. Kate Clifford Larson, whose 2015 biography Rosemary: The Hidden Kennedy Daughter is the most thorough account of Rosemary’s life, notes that this delay posed a genuine risk of oxygen deprivation. A prolonged restriction of oxygen during the birth process can cause damage to developing brain tissue.
The National Park Service, in its article on Rosemary Kennedy, states plainly that the cause of her intellectual challenges is unknown. The birth account appears in secondary sources based largely on Rose Kennedy’s own recollections, which were not recorded contemporaneously and which may have been shaped by years of family narrative. Whether oxygen deprivation during those two hours caused, contributed to, or coincided with Rosemary’s later developmental differences cannot be established with certainty from the available record.