The best feature is the festive setting. Christmas provides a magical backdrop of twinkling lights, snow, and warm fires, which sets a romantic mood. Another feature is the themes of hope and new beginnings often associated with Christmas. In 'Catching Christmas' novels, these themes enhance the romantic storylines.
One popular 'Catching Christmas' - type Christmas romance novel could be 'A Christmas Carol' by Charles Dickens. It has elements of love and redemption during the Christmas season. Another might be 'The Christmas Train' which combines a journey with budding romances during the holidays. And 'The Holiday' is also a great choice as it tells a story of love across different cultures during Christmas time.
Well, it could be the same mother or there could be some changes depending on the creative direction of the filmmakers. Maybe there are new elements introduced to add depth to the story.