CUTE.

As you may be aware, the Duke and Duchess of Cambridge welcomed their third child yesterday and the royal birth was featured in publications all over the world. There was rolling coverage from multiple news outlets all day and of course, Prince George and Princess Charlotte arriving to see their little brother was the source of much attention. Everyone noticed's Charlotte's wave to the cameras while George was quiet and didn't appear to take too much notice of the crowds waiting at St Mary's Hospital. However, what many of us missed was the protective gesture George, who turns five in July, made towards his little sister, set to celebrate her third birthday next month. As you'll see in the below video, dad William ushered them in the front door of the Lindo wing and you can just see George outstretch his arm to his younger sister.

Duke of Cambridge arrives at hospital with Prince George & Princess Charlotte following birth of their baby brother https://t.co/lGZ2YAK7um #royalbaby pic.twitter.com/PKt5yS5da2

— BBC Breaking News (@BBCBreaking) April 23, 2018

Eagle-eyed Twitter users were quick to pick up on it and it really is the cutest thing.

Prince George shifting to big brother mode after the cameras stopped clicking. He placed his arm around Princess Charlotte to keep her safe. Awwww, melts my ❤️❤️❤️ #royalbaby3 #PrinceGeorge #PrincessCharlotte #siblinggoals @KensingtonRoyal pic.twitter.com/c1jPgj4dCm

— royalblue_banker (@MatthenBenGol) April 23, 2018

The way Prince George put his arm around Princess Charlotte as they were walking in to The Lindo Wing! ? @SkyNews #RoyalBaby #royalfamily #PrinceGeorge #PrincessCharlotte

— Rach Heathcote (@rachyheathcote) April 23, 2018

DID GEORGE HUG CHARLOTTE AT THE END??? ?? https://t.co/E7Jm0ly4gA

— Sandra ?⚘ (@_MissKellyBiebs) April 23, 2018

George just gave Charlotte a hug inside??

— Royal highness (@HighnessN) April 23, 2018

A little moment of #PrinceGeorge wrapping his arm around little #PrincessCharlotte and Charlotte sticking out her little hand for George to hold. This is the cutest most precious thing... ? #RoyalBaby # pic.twitter.com/jYDbtRomaz

— Abiee Oliver (@AbieeOliver) April 23, 2018

The name of the new Prince has not yet been announced but that hasn't stopped people from speculating what the couple will choose. At the moment, Arthur, Albert, James and Phillip are among the frontrunners and all will be revealed in 'due course' according to Kensington Palace.