The beloved Kate Middleton and Prince William are expecting their second child.
The announcement came early Monday morning around 5:30 a.m. EST from the royal household's official Twitter account @ClarenceHouse.
Read the official statement below, which confirms that Kate, who is reportedly not 12 weeks pregnant, is again suffering from acute morning sickness as she did during her first pregnancy with Prince George, who she gave birth to just over a year ago:
Their Royal Highnesses The Duke and Duchess of Cambridge are very pleased to announce that The Duchess of Cambridge is expecting their second child.
The Queen and members of both families are delighted with the news.
As with her first pregnancy, The Duchess is suffering from Hyperemesis Gravidarum. Her Royal Highness will no longer accompany The Duke of Cambridge on their planned engagement in Oxford today. The Duchess of Cambridge is being treated by doctors at Kensington Palace.
ABC News royal contributor Victoria Murphy, who is in Oxford covering the royal event that Middleton was not able to attend today due to morning sickness, told ABC that 'the Palace would likely not have released news of Kate's pregnancy for another five to six weeks had she been healthy enough to attend public events.'
'It's not something that they would have wanted to do,' Murphy said. 'They had to announce it today because she was due to attend here today and she couldn't be here and they knew that there would be huge questions and speculation about why she wasn't here.'
The Press Association also explains the royal hierarchy as it will stand with the introduction of baby number two:
The new royal baby will be born fourth in line to the throne.
As a sibling to Prince George, the Duke and Duchess of Cambridge's second child will not be expected to be crowned sovereign.
But second-born royal children - often dubbed the "spare to heir" - have on occasion ended up as monarch.
The country's last king, George VI, was not meant to accede to the throne and only did so when his older brother Edward VIII abdicated over his love for American divorcee Wallis Simpson in 1936.
Once he or she arrives, Prince Harry will shift down the line of succession to fifth in line to the throne, while the Duke of York will move to sixth place and princesses Beatrice and Eugenie to seventh and eighth.
The baby will be a prince or princess thanks to the Queen, who stepped in ahead of Prince George's birth to ensure all William's children would become HRHs with fitting titles.
If the baby is a girl, it will be the first time a great granddaughter of a still-serving sovereign has been born in direct succession on the male line since 1897, when George VI's sister Princess Mary was born.
British PM David Cameron released a statement of congratulations Monday: "Many congratulations to the Duke and Duchess of Cambridge. I'm delighted by the happy news that they're expecting another baby."
An official aide also released in a tweet that Kate's schedule may experience interruptions likely due to morning sickness.
Report continues below:
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Confirmed: Duchess Kate is expecting royal baby #2!
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