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There's much speculation on who will receive an invite to the royal wedding and you'd think that with 2,000 seats there's enough space for everyone the royal family and the Middleton family want to invite, but the list will have to be cut at some point.
Many of the guests will be members of the royal family from Britain and around the world. From the Windsor family, it is expected that all of the Queen's children, their spouses and her grandchildren will be invited. Some royal sources have said that the former Duchess of York, Sarah Ferguson, will not receive a wedding invitation. Royals from around the world who will receive a wedding invitation include Crown Princess Victoria of Sweden and her new husband Prince Daniel Westling, Prince Albert of Monaco and his fiancé Charlene Wittstock, Prince Felipe and Princess Letizia of Asturias, Spanish King Juan Carlos I and King Abdullah and Queen Rania of Jordan.
Heads of state from almost every country in the world will be invited, including President and Mrs. Obama and President Nicolas Sarkozy and his wife Carla Bruni. At Prince Charles and Princess Diana's wedding in 1981 President and Mrs. Reagan were invited but only Nancy Reagan attended the wedding.
Members of the British government including Prime Minister David Cameron are sure to make the list too.
Since Prince William and Kate Middleton travel in A-list circles a number of high profile celebrities are sure to receive a wedding invitation including David and Victoria Beckham, Sir Elton John and Sir Paul McCartney. At Princess Diana's funeral, held at Westminster Abbey in 1997, Tom Cruise and Nicole Kidman, Tom Hanks and Rita Wilson, Steven Speilberg and Luciano Pavarotti were among the invited guests, so it's possible that some of Hollywood's biggest names will also be invited to the royal wedding.
Prince William and Kate Middleton are involved in a number of charities and will most likely want to invite representatives from many of the organizations they support.
Prince William and Kate Middleton have decided that 100 members of the British public will be invited to the wedding via a lottery drawing that's been compared to the "Golden Ticket" contest in Charlie and the Chocolate Factory.
The Middleton family will probably be given 100-200 invitation to invite their relatives and friends and Kate Middleton may be given her own batch of 50 wedding invitations to invite her friends.
One thing to be sure of is that security will be tight at Westminster Abbey in the weeks leading up to the wedding day so it is unlikely that someone will be able to crash the wedding of the century.
More on the Royal Wedding:
Britain's Top Wedding Dress Designers: What Kate Middleton's Wedding Dress Should Look Like
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See Kate Middleton's Engagement Ring -- It Was Diana's!
Who Is Kate Middleton, the Future Queen of England
23 Stunning Historical Royal Wedding Dresses