Prince Louis, the youngest child of Prince William and Kate Middleton, turned four on Saturday, and British Queen Elizabeth II wished him a happy birthday.

The Queen’s birthday greetings for Prince Louis were posted on the royal family’s official Twitter account, along with a charming photo of the baby prince.

“Happy 4th Birthday Prince Louis!” reads the message. Then there’s the birthday cake emoji.

The sweet photo of Prince Louis was taken by Kate Middleton in Norfolk earlier this month.

Earlier, Duke of Cambridge Prince William and his wife Kate Middleton celebrated the fourth birthday of Louis and mesmerized the royal fans with his adorable photos.

Kate posted the photos with caption, “4 years old tomorrow!”

Louis is a great-grandson of Queen Elizabeth II, and fifth in line to the throne, behind his grandfather Charles, father William and siblings George and Charlotte.