Prince William and Kate Middleton may be awaiting the arrival of their second child, but today is cause for another celebration for the couple—it's their fourth wedding anniversary! Four years ago today, everyone's favorite royal couple said "I do" in front of friends, family, and millions of viewers worldwide. Since then, it's clear that their bond has only gotten stronger. From the birth of Prince George to their multiple tours across the globe, there's been no shortage of aww-inspiring, love-filled moments between the two. Celebrate their fourth wedding anniversary by taking a look at their cutest couple moments in our gallery.