We sent a regrets RSVP to his cousin's wedding along with a $100 giftcard to the Keg. However we did not receive any thank-you note or acknowledgement that they got it. I'm wondering if it might've gotten lost in the mail. I have never met them and DH is not close to them (haven't spoke in years and do not have their contact).
Should we find a way to ask if they got it?