As he celebrates his 12th birthday today, the young royal has many people to turn to who will undoubtedly help steer him on ...

There are a lot of rules in the royal family - but there's one major regulation that kicks in when a future monarch turns 12.

Prince William will morph into King William pretty much the second King Charles passes away, and in that moment the title "Prince of Wales" will technically "ceases to exist," according to Brittanica.