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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