Duck Dynasty stars Mary Kate and John Luke Robertson are expecting - and even they admit the news caught them by surprise. "Absolutely thrilled to tell y'all we are welcoming TWINS to our family early next year!!! The most wonderful, crazy surprise blessing of our lives ha! Two new little Robertson girls!🩷🩷," Mary Kay wrote via Instagram on Friday, October 3, announcing her pregnancy. The pair are already mom and dad to three children: John, 6, Ella, 4, and Wells, 2.