Kennedy’s sister, Rosemary, who died a couple years ago, was retarded. Her condition inspired her younger sister, Eunice to found the Special Olympics.
I know all about Rosemary Kennedy.
She had a borderline low IQ and was showing signs of being promiscuous (which it seems is encouraged in Kennedy men but taboo for women). Joseph Kennedy Sr. was concerned that she would get pregnant and embarrass the family, so he had her lobotomized (which the inexperienced doctor botched) and put her in an institution. The Kennedy family then tried to hide the truth about what really happened.