See pics: Prince William and Kate Middleton pose with their newborn royal baby

The Duke and Duchess of Cambridge, Prince William and Kate Middleton, appeared on the steps of the Lindo Wing at St. Mary?s Hospital on Monday to introduce their new baby boy to the world. Wearing a red dress with a white collar, Middleton looked in good health after giving birth to her as yet un-named prince, who is fifth in line to the throne.
Prince William, while getting into his car, said, "We're very happy but thrice worried now."

The Kensington Palace, which is currently the official London residence of the Duke and Duchess of Cambridge, also posted pictures of Prince William, Kate Middleton, and their third child. "Welcome to the family," read a tweet.

Welcome to the family. pic.twitter.com/nKSd5kh5bZ

— Kensington Palace (@KensingtonRoyal) April 23, 2018

Earlier, Prince William took Prince George and Princess Charlotte to the St Mary's Hospital to meet their little brother. 

Prince George and Princess Charlotte arrive at St Mary’s to meet their little brother. pic.twitter.com/rfX9rsdJhU

— Kensington Palace (@KensingtonRoyal) April 23, 2018

Two-year-old Princess Charlotte waved happily to crowds outside the Lindo Wing on her way to meet her little brother. The new prince is the Queen's sixth great-grandchild.