Prince George and Princess Charlotte Dress in Blue to Meet Royal Baby No. 3 -- See the Adorable Pics!

Prince William and Kate Middleton's eldest children were spotted arriving to the hospital to meet their baby brother for the first time on Monday.

Prince George and Princess Charlotte have met their baby brother!

Shortly after Prince William and Kate Middleton welcomed their third child, a baby boy, at St. Mary's Hospital in London, England, on Monday, the Duke and Duchess of Cambridge's eldest children were photographed arriving at the hospital.

Adorably holding hands with their father, Prince George, 4, and Princess Charlotte, 2, appeared to be in good spirits, smiling and waving to photographers on their way into the institution.

All three of the royals were dressed in a shade of blue, subtly honoring the arrival of Kate and William's baby boy. It appears they took a fashion cue from Kate, who was seemingly giving us clues about the gender of royal baby No. 3 all along!

The Duke of Cambridge looked dapper in a dark blue blazer over a powder blue dress shirt, which he paired with navy slacks, while George looked as cute as ever in a matching dress shirt styled with a sweater, shorts and loafers. Princess Charlotte looked equally adorable, rocking a light blue patterned dress with an indigo blue cardigan.

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While walking up the stairs to the hospital, Charlotte proved she's already an expert at royalty by turning back to flash a smile for the photographers.

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It doesn't get much cuter than that!

A few hours after Kensington Palace initially announced the baby news, William was spotted leaving the hospital to tend to George and Charlotte. "Back in a minute," he told onlookers.  

Interestingly enough, the father of three even drove himself to and from the hospital, as documented by photographers and videographers on site.

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Kensington Palace revealed that the Duke and Duchess of Cambridge will leave St. Mary's Hospital on Monday evening, and their youngest son will travel home with them.

As we patiently wait to hear what the couple named their newborn, watch the video below to hear everything we know (so far!) about royal baby No. 3.

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