What the evidence does support, across multiple sources, is that the decision was Joe Kennedy’s, that he made it without his wife’s prior knowledge, and that the outcome was catastrophic and permanent. That is what can be said with confidence. What cannot be said with confidence is the exact interior of the decision — the private calculation, the degree of self-deception, the weight given to different considerations in a man’s mind in 1941 as he tried to solve a problem that had been part of his family’s life for twenty-three years.
The Age at Lobotomy: A Final Accounting
The prompt that guides this article raises the question of Rosemary’s exact age at the time of the lobotomy — a question worth addressing precisely because the historical record contains a minor discrepancy that has circulated in some sources.
Rosemary Kennedy was born on September 13, 1918. The lobotomy was performed in November 1941. The arithmetic is not complicated: in November 1941, Rosemary had already passed her twenty-third birthday, which fell in September 1941. She was, at the time of the surgery, twenty-three years old.
A JFK archives blog cited in the prompt gives the age as twenty-two. This would require the lobotomy to have been performed before September 13, 1941 — specifically, between January and September 12, 1941. The available evidence does not support this timing. Multiple sources, including the NPS article (which the prompt identifies as among the stronger sources on this question), place the lobotomy in November 1941. November comes after September. At the time of a November 1941 surgery, Rosemary would have been twenty-three years old.