The Prince George, which renamed itself after the royal tot last fall, will host a traditional British sing-along next week in honor of its namesake.
"We have a 'Royal Knees-Up Karaoke Party' planned with fancy dress and all British food. It's exciting," landlord Terry Rigg tells PEOPLE of his establishment in Watford, Hertfordshire, on the outskirts of London.
The pub debuted its new moniker last August, one month after the little prince was born, after Rigg appealed to locals to choose a new name for the struggling watering hole.
The majority voted to name it after the young prince, and Rigg, an enthusiastic royalist, felt it was only right to inform the royal family of his pub's new name.
He was both shocked and delighted when Princess Kate and Prince William responded.
"We got a letter back from Will and Kate with a lovely picture of the three of them," says Rigg, who added that the image is now proudly displayed on one of the pub's walls.
The wording of the letter: "The Duke and Duchess were touched that you would change the name of your pub to the Prince George and have asked me to send you and your customers their warmest thanks and best wishes."
Patrons at the birthday bash can get their picture taken next to the official letter – as they often do – and immerse themselves in all things royal.
All cocktails in the pub are named after royal family members, and the "Prince George" burger – which the little prince could surely sample if he stops in before he's eligible for a drink – is a menu staple.
Rigg says his establishment will keep a close eye on the royal tot's development – and plans to evolve right along with him.
“As he grows up, we will put more pictures up on the wall," he says. "It's fun and it's become a local tourist attraction."