Eunice Kennedy Shriver, the sister of former President John F. Kennedy and Sen. Ted Kennedy, who helped launch the Special Olympics, died at a Cape Cod hospital at 2 a.m., her family said. She was 88.
Shriver is survived by two siblings, her husband, Robert Sargent Shriver Jr., five children, including NBC reporter and California first lady Maria Shriver, and 19 grandchildren.
"She was the light of our lives, a mother, wife, grandmother, sister and aunt who taught us by example and with passion what it means to live a faith-driven life of love and service to others," the Shriver family said in a written statement. "For each of us, she often seemed to stop time itself -- to run another Special Olympics games, to visit us in our homes, to attend to her own mother, her sisters and brothers, and to sail, tell stories, and laugh and serve her friends."
"Her work transformed the lives of hundreds of millions of people across the globe, and they in turn are her living legacy," the statement said.
While she campaigned for her brother John's presidential campaign and was a frequent face in political and social circles around the country, Shriver is best known for her involvement with the Special Olympics and for helping establish the games 40 years ago.
"Above all, she will be remembered as the founder of the Special Olympics, as a champion for people with intellectual disabilities, and as an extraordinary woman who, as much as anyone, taught our nation -- and our world -- that no physical or mental barrier can restrain the power of the human spirit," President Obama said in a statement. "Her leadership greatly enriched the lives of Special Olympians throughout the world, who have experienced the pride and joy of competition and achievement thanks to her vision."
Born July 10, 1921, Shriver was the fifth of nine children of Joseph Kennedy and Rose Fitzgerald Kennedy.
Family members said she was inspired by her older sister, Rosemary Kennedy, who was mentally handicapped.
"Throughout her extraordinary life, she touched the lives of millions, and for Eunice that was never enough. The seeds of compassion and hope she planted decades ago in her backyard summer camp were inspired by her love for our sister Rosemary," Shriver's brother, Sen. Kennedy, D-Mass., said in a written statement.
"Over the years, she grew those seeds into a worldwide movement that has given persons with disabilities everywhere the opportunity to lead more productive and fulfilling lives. We would never have had an Americans with Disabilities Act without her," Kennedy said.
In a February "Good Morning America" special spotlighting Shriver, Kennedy said his sister was tireless in her efforts.
"Eunice would spend the extra time with Rosemary, teaching her and making sure that she felt included," he said. "It was really that spirit that started the Special Olympics. Eunice is tireless and fearless and reflects a sense of goodness, so it's very difficult for people to say no to Eunice."
It was Shriver's goal to attain equality for the mentally challenged, and she believed they could excel despite their handicaps.
"I love to be with my special friends, and I like to learn from them and their persistence, and their guts, and their courage," Shriver said of her work with athletes with disabilities. "This is the future."
Shriver's friends say she took personal tragedy and transformed it into a movement that changed the lives of millions of people.