What do Justin Bieber, President Obama, Taylor Swift and Queen Elizabeth II have in common? They have all made headlines this year crashing weddings. While many brides wouldn’t be angry if these celebs crashed their wedding day — check out our list of celebrities that you don’t want showing up unannounced at your wedding.

> The Knot’s guide to spotting a wedding crasher

> Taylor Swift crashed the wedding of her boyfriend’s cousin

> How to deal with wedding crashers