William & Kate's Ark Gala Dinner Date: All the Details!

Kate Middleton's Duchess duties have begun!

The 29-year-old newlywed joined Prince William, 28, at the ARK 10th Anniversary gala in London Thursday. Held at Kensington Palace, Middleton sat next to Prince Pavlos of Greece while her husband sat in-between Marie Chantal of Greece and Debbie von Bismarck.

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Other guests at their table included designer Tom Ford, Arpad 'Arki' Busson, Elisabeth Murdoch, Helen Asprey, Lord Janvrin, Countess von Bismark, Jemima Khan, Baroness de Rothschild and Jamie Lowther-Pinkerton.

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Despite the fact that they didn't sit next to each other, the newlyweds were constantly "looking at each other and smiling", a guest tells Us Weekly. "They were almost smirking. It was cute. Like they were trying not to giggle."

Both William and Kate opted for the Kobe beef as their main course. "Kate ate a lot!" an onlooker tells Us of the Jenny Packham-clad royal. "I don't know where she puts it!"

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Before William addressed the attendees, guests listened to stories about disadvantaged children around the world. "Kate looked touched," says a guest. "She didn't cry, but her face showed a lot of emotion." (Middleton is now a part of the Foundation for Prince William and Prince Harry; it has since been renamed the Foundation of Prince William and Prince Harry and The Duchess of Cambridge.)

William then spoke of a "new joint initiative between ARK and The Foundation of Prince William and Prince Harry. [This is a] joint venture based on our shared vision and commitment to transform lives of thousands of young people," he said.

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"I know I am fortunate, have had a good education, secure home, loving and supportive family," he told the crowd, which included Elizabeth Hurley, David Furnish, Kevin Spacey and Colin Firth. "So many do not have these advantages, which is why I am pleased the Foundation and ARK are working together."

After receiving a standing ovation, the royal couple made an early exit, leaving before Mark Ronson and Kings of Leon took the stage. By the end of the knight, a whopping $28 million had been raised on behalf of Absolute Return for Kids (ARK).