The most eagerly awaited pregnancy was announced today by St. James Palace on behalf of Middleton and her husband Prince William.
The child, whether boy or girl, will eventually be heir to the British throne according to new legislation awaiting final approval.
Kate, 30, who is less than 12 weeks pregnant, has been on a drip to restore lost nutrients since being driven to the King Edward VII Hospital in central London by her husband yesterday.
MailOnline sources today confirmed the Duchess is bearing up well - but her symptoms of severe vomiting may last for much of Kate Middleton pregnancy.
THE ROYAL WEDDING IN PHOTOS The ancient rule of royal primogeniture was scrapped last year to allow girls to ascend to the throne ahead of any younger male heirs after the Brits reached an agreement with the reached an agreement between heads of the Commonwealth nations.