Prince William and Kate Middleton just celebrated their wedding anniversary with a romantic vacation public engagement in Scotland, so naturally everyone's been busy looking back at their royal wedding. And while there were a lot of cute moments (this lip reading of William at the altar!), there were some awkward ones too.

The Daily Mail is out here reporting that William invited not one, not two, not three, but FOUR of his ex-girlfriends to the wedding. First up, Isabella Anstruther-Gough-Calthorpe, who he dated in the summer of 2004. Then there was Arabella Musgrave (his girlfriend in the summer before he went to St Andrews and met Kate), not to mention his very first girlfriend Rose Farquhar, AND his ex Jecca Craig aka his "first true love."

guy ritchie (c) and isabella calthorpe (r) arrive to attend the royal wedding of prince william to catherine middleton at westminster abbey on april 29, 2011 in london, england. the marriage of the second in line to the british throne is to be led by the archbishop of canterbury and will be attended by 1900 guests, including foreign royal family members and heads of state. thousands of well wishers from around the world have also flocked to london to witness the spectacle and pageantry of the royal wedding.
Danny Martindale
Isabella Anstruther-Gough-Calthorpe at William and Kate's royal wedding

Turns out it's something of a royal tradition to invite exes to one's wedding (help), and William isn't alone. Queen Camilla was at Prince Charles' wedding to Princess Diana, and several of Prince Harry's exes were at his wedding to Meghan Markle.

"I think it is one of the determining details of the upper-class species that they keep friendly with their exes, once the pain of the breakup heals," William Norwich told The New York Times at the time of Will and Kate's wedding. "It is custom of the class. Sustaining hostilities is too down-market. You may split up, but if you want to stay in the club, you better get along. You still want to get invited to Ascot."

Oh, and for what it's worth, Kate also invited her exes to the royal wedding: Rupert Finch (who she dated before Prince William) and Willem Marx (her high school boyfriend)!