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Prince William's Joke About Kate Middleton's Birthday To A Little Girl Is The Sweetest

Despite his busy schedule, Prince William knows exactly what day it is. Wednesday, Jan. 9, marks a special day in his wife's life and Prince William's joke about Kate Middleton's birthday is sure to make anyone laugh, even if doing so breaks royal protocol.

While attending a public engagement at the Royal London Hospital, William was met by a young admirer who delivered a handmade birthday card for the Duchess of Cambridge that read, "Kate, I hope you've had the best birthday you could ever imagine." William praised the girl for remembering and also added that he too had remembered her birthday sharing, "I did remember this morning, so I was ok," as those around him giggled at his remark.

Prince William was announced as the patron of the air ambulance’s 30th Anniversary Campaign Wednesday with the Palace releasing a statement that said, "As Patron of the 30th Anniversary Campaign, the duke will champion those working on the frontline, and highlight the importance of the London Air Ambulance’s vital work."

And despite it being Kate's birthday, it's not out of the ordinary for members of the royal family to make public outings during important life events. Just back in November, the royal couple visited the homelessness charity Centrepoint hours before they were set to attend Prince Charles' 70th birthday at Buckingham Palace.

According to PEOPLE, Prince William was also gifted with a set of toys to bring home to his three children — Prince George, Princess Charlotte, and Prince Louis.

“Look at these, they are amazing! That will go down very well. Louis will be chewing that before long," Prince William said, referring to a plush helicopter.

Although it hasn't been revealed what exactly William and Kate have in store for her birthday, it can certainly be assumed that the two will spend it intimately with their three children and the rest of their family, celebrating what is sure to be another phenomenal year.

Kate's birthday also comes only weeks after Christmas, which the family was said to have spent with both William and Kate's side of the family, as highlighted by Kate's mother Carole Middleton in an interview with The Telegraph and confirmed by a palace source to BAZAAR.com. Kate's mother shared that the family would be at Sandringham with William's side of the family on both Christmas Eve and Christmas Day.

Speaking about their plans for the days after Christmas, Kate's mother shared, "I try not to be too set when it comes to the schedule."

This past Christmas also marked William and Kate's first Christmas celebrated with Kate's youngest son, Prince Louis, and the latest addition to her family, Pippa Middleton's son Arthur Matthews.

But no matter how Kate decided to spend her birthday we can only hope it was one of her best and that the heartwarming card she received today was just one of the many special mementos she will have from this special day.