Britain's Prince William laughed when he was introduced as his grandfather on Friday (21.11.14).
The 32-year-old royal saw the funny side at a ceremony at the Royal United Services Institute in Whitehall, London when he was presented as the Duke of Edinburgh, the official title of his grandpa Prince Philip.
William - whose wife Duchess Catherine is expecting their second child - brushed off the toastmaster's gaffe to hand out the Chatham House Prize to Bill Gates' wife Melinda in recognition of her humanitarian work through the Gates Foundation, which helps provide increased access to family planning, better nutrition and life-saving vaccines.
William told assembled dignitaries including Sir John Major, Lord Ashdown and former UN secretary-general Kofi Annan: "With her equally remarkable husband Bill, Melinda set up the Gates Foundation to change the world.
"And change it she has, transforming the lives of women, the poor, the sick and the disadvantaged in Africa and elsewhere.
"The Queen, who has been patron of Chatham House since 1952, sends you this message, which I have the honour of reading now, 'I send my warmest wishes and congratulations to Melinda Gates on being awarded this year's Chatham House Prize for her humanitarian work and her long-standing commitment to philanthropy. Members of the Royal Institute of International Affairs have chosen a worthy winner.' "
Melinda said she was honoured to receive the work and very proud of the achievements of her charity.
She said: "I sometimes wish we could take your public here and let them witness first hand what Bill and I have witnessed around the world.
"Since 1990 we have cut in half the number of children who have died under the age of five. At the same time the population has grown by two billion.
"That is incredible. We have a chance again in the next decade, in the next 15 years, to cut that number in half again."
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