Prince William and Duchess Kate debut third child Prince Louis: See the photos

Prince William and Duchess Kate debuted their new baby boy — their third child, His Royal Highness Prince Louis of Cambridge — on the steps of St. Mary's Hospital in London on April 23, 2018, just hours after his arrival. Wonderwall.com rounded up the best photos of the royal baby's debut. Keep reading to take a look…

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This is a closeup of Prince William and Duchess Kate's third child, Prince Louis, leaving the Lindo Wing at St. Mary's Hospital in London on April 23, 2018.

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Prince William and Duchess Kate leave the Lindo Wing at St. Mary's Hospital in London with their newborn baby boy, Prince Louis, on April 23, 2018.

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Prince William and Duchess Kate leave the Lindo Wing at St. Mary's Hospital in London with their newborn baby boy on April 23, 2018.

Duchess Kate leaves the Lindo Wing at St. Mary's Hospital in London with her newborn baby boy, Prince Louis, on April 23, 2018.

Duchess Kate and Prince William leave the Lindo Wing at St. Mary's Hospital in London with their newborn baby boy, Prince Louis, on April 23, 2018.

Prince William and Duchess Kate leave the Lindo Wing at St. Mary's Hospital in London with their newborn baby boy on April 23, 2018.

Prince William carries his newborn third child while leaving the hospital in London on April 23, 2018.

Prince William and Duchess Kate leave the Lindo Wing at St. Mary's Hospital in London with their newborn baby boy on April 23, 2018.

Prince William and Duchess Kate leave the Lindo Wing at St. Mary's Hospital in London with their newborn baby boy on April 23, 2018.

Prince William and Duchess Kate leave the Lindo Wing at St. Mary's Hospital in London with their newborn baby boy on April 23, 2018.

A closeup of Prince William and Duchess Kate's third child leaving the Lindo Wing at St. Mary's Hospital in London on April 23, 2018.

Prince William and Duchess Kate wave as they leave the Lindo Wing at St. Mary's Hospital in London with their newborn baby boy on April 23, 2018.

Prince William and Duchess Kate leave the Lindo Wing at St. Mary's Hospital in London with their newborn baby boy on April 23, 2018.

Prince William and Duchess Kate leave the Lindo Wing at St. Mary's Hospital in London with their newborn baby boy on April 23, 2018.

Duchess Kate holds her newborn baby boy while leaving the hospital in London on April 23, 2018.

Prince William takes Prince George and Princess Charlotte to meet their newborn brother for the first time at St. Mary's Hospital in London on April 23, 2018.

Prince William takes Princess Charlotte and Prince George to meet their newborn brother for the first time at St. Mary's Hospital in London on April 23, 2018.

Princess Charlotte arrives to meet her new brother at the Lindo Wing at St. Mary's Hospital in London on April 23, 2018.

Prince William and Duchess Kate leave the Lindo Wing at St. Mary's Hospital in London with their newborn baby boy on April 23, 2018.