The Duke and Duchess of Cambridge posted two photos of Louis on their shared Instagram account, showing the prince smiling and laughing on a beach. Four photos of Louis were released by Kensington Palace on Friday. The portraits were taken by Kate earlier this month in Norfolk, England.
“4 years old tomorrow!” the post reads.
In the pictures, Louis appears to be playing and running on the sandy beach while wearing teal shorts and a star-print gray sweater.
Louis was born on April 23, 2018, becoming fifth in line to the throne behind his older siblings, Prince George and Princess Charlotte.
The royal couple have traditionally shared portraits of their three children each year in celebration of their birthdays.