Kate Middleton had to follow a strict Royal rule when she gave birth to Prince George, and it meant she couldn't even tell her own mum about the happy news.
George, who is the future heir to the throne, was born on 22 July 2013, causing a media frenzy as everyone wanted to see the first photo of the newborn.
But what many people might not know is that Kate had to keep the birth a secret until one very important person was told - the Queen.This is because of a Royal protocol that says no one can know about the birth of a future monarch until the current monarch has been told.
So, Kate wasn't allowed to tell her parents, other family members or friends until the Queen knew about her great-grandson's arrival.
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