Prince William and Duchess Kate are continuing a royal family tradition in honour of a very special occasion. On Thursday, the Duke and Duchess of Cambridge shared a new photo of their son Prince Louis, just a day before he turns three!

Prince Louis rides bike in photo taken by mom Kate

William and Kate took to Instagram to share the never-before-seen photo of Prince Louis. In the picture, Louis can be seen wearing a navy sweater and shirt with blue shorts. He gives a toothy grin as he smiles for the camera, while sitting on top of a shiny red bicycle.

In the caption, the royals explain that the photo of Louis was taken by Kate "before he left for his first day of nursery" sometime this week. The Duke and Duchess of Cambridge also shared new photos of their youngest son last year, in honour of his second birthday.

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Since Louis is still just a few years old, the young prince has only made a few public appearances so far! In December, he was seen stepping out for a night at the theatre with his family, as they attended a special pantomime performance that honoured frontline workers.