Prince William greets Kate Middleton as she arrives at the alter with her father Michael Middleton, prior to their marriage in London's Westminster Abbey, Friday April 29 2011.(AP Photo/ Dominic Lipinski, pool)
FILE - In this Friday April 29, 2011 file photo Britain's Prince William and his bride Kate, Duchess of Cambridge, leave Westminster Abbey, London, following their wedding. (AP Photo/Tom Hevezi, File)
Prince William greets Kate Middleton as she arrives at the alter with her father Michael Middleton, prior to their marriage in London's Westminster Abbey, Friday April 29 2011.(AP Photo/ Dominic Lipinski, pool)
Britain's Prince William and Kate Middleton exchange rings in front of the Archbishop of Canterbury at Westminster Abbey, London, Friday April 29, 2011. (AP Photo/Dominic Lipinski, Pool)
Britian's Prince William, left, and Kate Middleton with her father Michael Middleton singing during their wedding at London's Westminster Abbey, Friday April 29, 2011. (AP Photo/Dominic Lipinski, Pool)
In this image taken from video, Britain's Prince William, left, places the ring on the finger of his bride, Kate Middleton, as they stand at the altar at Westminster Abbey for the Royal Wedding in London on Friday, April, 29, 2011. (AP Photo/APTN) EDITORIAL USE ONLY NO ARCHIVE PHOTO TO BE USED SOLELY TO ILLUSTRATE NEWS REPORTING OR COMMENTARY ON THE FACTS OR EVENTS DEPICTED IN THIS IMAGE
In this image taken from video, Britain's Prince William, left, places the ring on the finger of his bride, Kate Middleton, as they stand at the altar at Westminster Abbey for the Royal Wedding in London on Friday, April, 29, 2011. (AP Photo/APTN) EDITORIAL USE ONLY NO ARCHIVE PHOTO TO BE USED SOLELY TO ILLUSTRATE NEWS REPORTING OR COMMENTARY ON THE FACTS OR EVENTS DEPICTED IN THIS IMAGE
Palace officials announced Monday that Prince William and Kate are expecting their first child.
"Their Royal Highnesses The Duke and Duchess of Cambridge are very pleased to announce that The Duchess of Cambridge is expecting a baby," the announcement said. "The Queen, The Duke of Edinburgh, The Prince of Wales, The Duchess of Cornwall and Prince Harry and members of both families are delighted with the news."
The announcement added that the duchess, 30, was admitted to King Edward VII Hospital in London on Monday with Hyperemesis Gravidarum, a severe form of morning sickness. She is expected to stay in the hospital for "several days" and "will require a period of rest thereafter."
As the first born to William, 30 - who is second in line to the throne after his father, Prince Charles - the couple's first child stands an excellent chance of one day becoming monarch.
Whether boy or girl, the child will be behind William in the line of succession to the throne, Cabinet Office officials said.
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