Kate Middleton and Prince William debut royal baby No. 3: Pictures!

Say hello to the prince!

Kate Middleton and Prince William debuted their third child on the steps of the Lindo Wing in London on Monday evening hours after Middleton gave birth to their new baby boy.

Kate and Will were all smiles as they held their new bundle of joy in front of an adoring crowd of fans and media. Middleton wore a red Jenny Packham dress with a white lace collar and stilettos, while Will opted for a light blue button-down under a classic blue blazer.

See photos from the royal baby No. 3's debut:

SEE ALSO: Kate Middleton gives birth to her third child: The royal baby is here!

The moment came hours after William was seen walking Prince George and Princess Charlotte into the hospital to meet their new baby brother. They reportedly left through a back entrance after a short visit to return to Kensington Palace.

After debuting their unnamed newborn, who weighs 8 pounds 7 ounces, Kate and Will walked back into the hospital, only to emerge moments later with their baby in a car seat before driving off to return home.

SEE ALSO: Kate Middleton's newborn son is the biggest royal baby to be born in over 100 years

The Duke and Duchess of Cambridge are expected to announce the name of their third child in the coming days. Royal experts think that James, Albert, Philip and Arthur are frontrunners for the fifth in line to the throne.

See photos of Prince George and Princess Charlotte's visit:

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