The beaming parents debuted their new baby on the steps outside the Lindo Wing just after 3AM Australian time, with the royal couple clearly thrilled to introduce their second son to the world.
A glowing Kate, wearing a red Jenny Packham smock dress, which is a sweet tribute to Princess Diana, who also wore red when she stood on the same steps with Prince Harry in 1982.
Proud dad William said to the waiting media, "we're very happy" before the couple headed back inside to gather their things before reemerging with the baby in a car capsule ready to go home.
"Very happy but we've now got thrice the worry," joked Wills as he packed the car.
"At least we didn't keep you waiting."
Siblings Prince George and Princess Charlotte were also taken to the hospital to meet their little brother.
The royals are yet to release a name for the newest family member.