Some wedding etiquette is applicable to most traditional Western Christian ceremonies. However, things can get a bit tricky when it comes to royal weddings. Sure, you shouldn't wear white or black, but did you know that taking pictures is also a no-no? But there's more, a lot more! Many celebrity guests, however, didn't get the memo and indeed broke tradition at royal weddings.
Click through the following gallery to discover who they are and what they did.