Obama shakes hands with Castro during a memorial service for former South African President Nelson Mandela in Soweto, South Africa, on Dec. 10, 2013. Former Cuban leader Fidel Castro says his brother introduced himself to Obama in English, telling him, "Mr. President, I'm Castro," as the two leaders shook hands. AP hide caption

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Fidel Castro, seen here in July, was awarded the Confucius Peace Prize, China's version of the Nobel Prize. He was not on hand to receive the award at a ceremony in Beijing on Tuesday. Alex Castro/AP hide caption

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In what could be a first, Mariela Castro (center), daughter of Cuban President Raul Castro, voted against legislation in the country's parliament. In May, she marched in a parade for the International Day Against Homophobia in Havana. Franklin Reyes/AP hide caption

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A visitor watches pictures taken by Cuban photographer and cinematographist Alex Castro, son of former Cuban president Fidel Castro. Alfredo Estrella/AFP/Getty Images hide caption

itoggle caption Alfredo Estrella/AFP/Getty Images