The British royal family has officially grown by one, with Catherine, the Duchess of Cambridge, giving birth to her third child today (April 23).

Her husband, Prince William, Duke of Cambridge, was with her at the time of arrival, welcoming their second son at 11:01 BST (6:01am EST). The baby prince, who has yet to be named, weighed 8lb 7oz at birth, reports BBC News.

A formal notice has been placed on the forecourt of Buckingham Palace for the public to view. If you're not in London, England, at the moment, no need to fret, the royal family has a Twitter account:

https://twitter.com/RoyalFamily/status/988413463805472768

The framed announcement will be on display for approximately 24 hours, and then the notice will be sent to the Privy Council for recording.

Here's a closer look with the exact wording:

[caption id="attachment_425975" align="alignnone" width="2000"] (Photo: Getty Images)[/caption]

The new baby joins brother Prince George, 4, and Princess Charlotte, 2. He is fifth in line for the throne.

Kensington Palace tweeted a video of Prince William, newly father of three, leaving St. Mary's Hospital to check in on George and Charlotte. Saying to the crowd, "Back in a minute. Back in a minute."

https://twitter.com/KensingtonRoyal/status/988437720719593473?tfw_site=GMA&ref_src=twsrc%5Etfw&ref_url=https%3A%2F%2Fwww.yahoo.com%2Fgma%2Fbritish-royals-princess-kate-prince-william-set-welcome-073804928--abc-news-celebrities.html

Here he is returning with the two older siblings to greet their new little brother:

[caption id="attachment_425955" align="alignnone" width="2000"] (Photo: Getty Images)[/caption]

We are very happy for the royal couple and their growing family!

[caption id="attachment_425980" align="alignnone" width="2000"] (Photo: Getty Images)[/caption]

You can catch up with the Duke and Duchess at the wedding of Prince Harry and American actress Meghan Markle on BBC America, airing May 19.

Do you have any name suggestions?