Thank you cards. It’s been my experience that it isn’t rare to hear those three words followed by an exuberant sigh or a collective eye roll. They seem like just one more thing on the ever-growing wedding to-do list and, quite frankly, are often at the bottom of the priority list when it comes to post-wedding life. But, to your guests, those little notes are much more than a polite “thank you” for a present.