Royal fans celebrate outside Windsor Castle in Berkshire after Buckingham Palace announced the news of the birth of a baby boy born to Prince Harry and Meghan Duchess of Sussex, Monday May 6, 2019.  It is the first child for Harry and Meghan, who married a year ago.  (Dominic Lipinski/PA via AP)
Royal fans celebrate outside Windsor Castle in Berkshire after Buckingham Palace announced the news of the birth of a baby boy born to Prince Harry and Meghan Duchess of Sussex, Monday May 6, 2019. It is the first child for Harry and Meghan, who married a year ago. (Dominic Lipinski/PA via AP)
An unofficial Town Crier announces the birth of a baby boy born to Britain's Prince Harry and Meghan, the Duchess of Sussex, outside Windsor Castle in Windsor, south England, Monday May 6, 2019, after Prince Harry announced that his wife Meghan, Duchess of Sussex, has given birth to a boy. (AP Photo/Alastair Grant)
An unofficial Town Crier announces the birth of a baby boy born to Britain's Prince Harry and Meghan, the Duchess of Sussex, outside Windsor Castle in Windsor, south England, Monday May 6, 2019, after Prince Harry announced that his wife Meghan, Duchess of Sussex, has given birth to a boy. (AP Photo/Alastair Grant)
Members of the media gather outside Windsor Castle in Windsor, south England, Monday May 6, 2019, after Prince Harry announced that his wife Meghan, Duchess of Sussex, has given birth to a boy. (AP Photo/Alastair Grant)
Members of the media gather outside Windsor Castle in Windsor, south England, Monday May 6, 2019, after Prince Harry announced that his wife Meghan, Duchess of Sussex, has given birth to a boy. (AP Photo/Alastair Grant)
Footmen Stephen Kelly and Sarah Thompson bring out the easel in the forecourt of Buckingham Palace to formally announce the birth of a baby boy to  Britain's Prince Harry and Meghan, the Duchess of Sussex, in London, Monday, May 6, 2019. (Yui Mok/Pool Photo via AP)
Footmen Stephen Kelly and Sarah Thompson bring out the easel in the forecourt of Buckingham Palace to formally announce the birth of a baby boy to Britain's Prince Harry and Meghan, the Duchess of Sussex, in London, Monday, May 6, 2019. (Yui Mok/Pool Photo via AP)
Well wishers gather outside the gates of Buckingham Palace in London, Monday May 6, 2019, after Prince Harry announced that his wife Meghan, Duchess of Sussex, has given birth to a boy.  (AP Photo/Vudi Xhymshiti)
Well wishers gather outside the gates of Buckingham Palace in London, Monday May 6, 2019, after Prince Harry announced that his wife Meghan, Duchess of Sussex, has given birth to a boy. (AP Photo/Vudi Xhymshiti)
Well wishers gather outside the gates of Buckingham Palace in London, Monday May 6, 2019, after Prince Harry announced that his wife Meghan, Duchess of Sussex, has given birth to a boy. (AP Photo/Vudi Xhymshiti)
Well wishers gather outside the gates of Buckingham Palace in London, Monday May 6, 2019, after Prince Harry announced that his wife Meghan, Duchess of Sussex, has given birth to a boy. (AP Photo/Vudi Xhymshiti)
Twitter was caught in a whirlwind on Monday after it was announced that the Duke and Duchess of Cambridge were about to welcome their first child, and before we knew it, news followed that the former "Suits" actress had given birth to a healthy baby boy.

Londoners also spent hours outside Buckingham Palace awaiting news of the royal baby's birth, and s oon after the official announcement on their Royal Sussex Instagram page, social media was flooded with congratulatory wishes for the new parents.

A visibly excited Harry also made a press appearance outside Windsor Castle where he shared the news of the baby's arrival, adding that Meghan and baby are doing well. The couple will reveal the baby and his name on Wednesday.

See some reactions below.