The princes wore matching outfits to visit the newest royal.
The little princess is getting her first royal visit: From her big brother, Prince George!
Prince William -- a dad of two as of early this morning -- went to fetch his heir to come and meet the spare.
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"I'm going to pick up George!" he told the crowd as he got into a black SUV.
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A few minutes later, he arrived back at St. Mary's with George. They're wearing matching outfits!
George, who will turn 2 in July, waved to the crowds, which probably included a lot of people who were there for his birth in July 2013.
Will kissed George and they waved to the crowd in their matching blue sweaters.
Kate and Will are expected to debut the newest addition to their family shortly.
In late March, Kate made her final appearance in public before having baby No. 2 in a pink coat, perhaps predicting we could expect a princess!