The only daughter and eldest child of the late Senator Edward Kennedy, Kara, has died of heart failure aged 51, her brother Patrick has said.
The former TV producer was in remission after having a malignant tumour on her lung removed in 2003. She had been weakened physically, he said.
In recent years, Kara Kennedy Allen worked for a charity involved in providing arts opportunities for the disabled.
Senator Kennedy died in August 2009.
She received the Presidential Medal of Freedom on his behalf from President Obama just 13 days before her father's death.
She is survived by brothers Patrick, a former congressman from Rhode Island, and Edward Junior, a lawyer and investment banker, her mother Joan Kennedy and a teenage son and daughter.
http://www.bbc.co.uk/news/world-us-canada-14960221
Note: 17 September 2011 Last updated at 18:47 GMT