WORLD: JFK's sister Eunice Shriver dies aged 88

Mrs Shriver had been critically ill in Cape Cod hospital, Massachusetts, since last week. A family statement said she died this morning.

She was the mother of TV star Maria Shriver and mother-in-law of California governor Arnold Schwarzenegger, but was most famous for organising the first Special Olympic Games in 1968.

Her efforts, inspired by her handicapped sister Rosemary, were credited with transforming America's view of the mentally disabled from institutionalised patients to friends, neighbours and athletes.

"Her work transformed the lives of hundreds of millions of people across the globe and they in turn are her living legacy," her family said. "We have always been honoured to share our mother with people of good will the world over who believe, as she did, that there is no limit to the human spirit."

President Obama today called her "an extraordinary woman". She had "taught our nation — and our world — that no physical or mental barrier can restrain the power of the human spirit".

Mrs Shriver's siblings also included Robert Kennedy, and sole surviving brother Senator Edward Kennedy, who has been battling a brain tumour.

She was married to Sargent Shriver, whose long public service career included starting the Peace Corps when JFK was president.

A 1960 Chicago Tribune profile of the women in the family said she was "generally credited with being the most intellectual and politically minded of all the Kennedy women", while Peter Collier, author of The Kennedys, an American Drama, called her the "moral force" of the clan. When her brother was in the White House, she pressed for efforts to help troubled young people and the mentally disabled.

In 1968, she started the world's largest athletic competition for mentally disabled children and adults. Now, more than a million athletes in more than 160 countries participate in Special Olympics meetings each year.

"When the full judgment on the Kennedy legacy is made — including JFK's Peace Corps and Alliance for Progress, Robert Kennedy's passion for civil rights and Ted Kennedy's efforts on health care — the changes wrought by Eunice Shriver may well be seen as the most consequential," wrote Harrison Rainie, author of Growing Up Kennedy. Her pioneering work crossed party lines and, well into her 80s, she was still in the US Capitol lobbying support for her causes.

Her death means that Jean Kennedy Smith becomes the last surviving Kennedy daughter.