What was Rosemary Kennedy's mental capacity / mental age was?

Rosemary Kennedy was the mentally handicapped sister of President John Fitzgerald Kennedy, Senator Robert Kennedy, Senator Ted Kennedy, and Eunice Kennedy Shriver. What (do you suppose) was Rosemary Kennedy's mental age (like Sean Penn in I AM SAM playing a single father with the mental age of a 7 year old like his little daughter)? Did she ever have any explosive outbursts and throw horrific fits? What issues did she have? Did she have any habits? What was she capable of doing? What was her IQ? Was it borderline? mild? moderate? or severe mental retardation?

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What was Rosemary Kennedy's mental capacity / mental age was?
Rosemary has been described as being a shy child whose I.Q. tests reportedly indicated a moderate mental retardation.



Placid and easygoing as a child and teenager, the maturing Rosemary became increasingly assertive in her personality. She was reportedly subject to violent mood swings. Some observers have since attributed this behavior to her difficulties in keeping up with her active siblings, as well as the hormonal surges associated with sexual maturation (puberty). In any case, the family had difficulty dealing with the often-stormy Rosemary, who had begun to sneak out at night from the convent where she was being educated and cared for.



In 1941, when Rosemary was 23, her father was told by her doctors that a lobotomy would help calm her "mood swings that the family found difficult to handle at home".



Instead of producing the hoped-for result, however, the lobotomy reduced Rosemary to an infantile mentality that left her incontinent and staring blankly at walls for hours. Her verbal skills were reduced to unintelligible babble. Her mother, Mrs. Rose Kennedy remarked that although the lobotomy stopped her daughter's violent behavior, it left her completely incapacitated.



Researchers disagree over the initial assessment of Rosemary's condition. According to the author Laurence Leamer, Rosemary Kennedy was "probably the first person with mental retardation in America to receive a prefrontal lobotomy". Mr. Kessler disagrees with this assessment; he believes that Rosemary's problem was instead mental illness. To support this theory, he points out that Rosemary was slower than the other children, spoke later, had reading problems, and could not keep up with her schoolwork. Joseph Kennedy's aide, Edward Moore, with whom Rosemary lived for years before the Kennedy family moved to London for Kennedy's ambassadorship, said, "She's not quite right", tapping his head. Returning from London at the age of 22, Rosemary apparently regressed in mental skills, became "tense and irritable, upset easily and unpredictably … tantrums … rages … convulsive episodes".



Kathleen Kennedy's former boyfriend, John White, claimed that Kathleen admitted to him the secret that Rosemary had learning problems — but what really concerned her father were "mood changes" and a "new neurological disturbance." She added that "the family considered Rosemary a disgrace and failure'".



Kessler also conducted an interview with the now-discredited Dr. Watts who "told the author that, in his opinion, Rosemary had suffered not from mental retardation, but from a form of depression. … 'It may have been agitated depression, you're agitated, you're shaky. You talk in an agitated way.'"



"A review of all records by the two doctors confirmed Dr. Watt's [sic] declaration. … None of the papers listed any of the patient as being mentally retarded. … According to a review in the American Journal of Psychiatry, of all reports of lobotomies ever done, the procedure was only used for psychiatric illness"



"One of the doctors who knew the truth was Dr. Bertram S. Brown, … executive director of the President's Panel on Mental Retardation," Kessler writes. "According to Dr. Brown, the fact that Rosemary could do arithmetic meant that her IQ was well above 75, the cutoff used by most states for purposes of classification in schools to define mental retardation." At the age of nine, she did problems like 428 x 32 = 13696, 3924 / 6 = 654. At age 16 she wrote to her father "I would do anything to make you so happy. I hate to disapoint [sic] you in anyway [sic]." Her diary reveals an ability to write about and understand various situations around her.



"If she did division and multiplication, she was over an IQ of 75. She was not mentally retarded. … It could be she had an IQ of 90 in a family where everyone was 130, so it looked like retardation, but she did not fall into IQ 75 and below, which is the definition of mental retardation. … There is no way I can picture her at less that a 90 IQ, but in that family, 90 would be considered retarded."