The shared Instagram account for Kate Middleton and Prince William welcomed a trio of guest posters Sunday, when children Prince George, Princess Charlotte, and Prince Louis took the platform over. The occasion: Father's Day, with a post in tribute to their dad, the Prince of Wales.

Royal fans have been left totally divided over one small detail in a rare ‘casual’ photo of Prince William and Kate Middleton with their three children.

For the post, the mom of three included a short but sweet message, writing, "Happy Father’s Day, Papa (before and after!) We love you! G, C & L 💖." Middleton also tagged the