The Andersen family's Christmas secret

Santa #39 has not done his job properly. Consequently, he must retake his Santa exam. If he fails, he will be demoted to an elf. Together with his assistant, Frits, he is assigned an exam task: to get a family that no longer celebrates Christmas to start celebrating it again. A draw assigns him the anti-Christmas Andersen family (father Tage, mother Åse, and daughter Putte). They harbor a terrible secret regarding why they do not celebrate Christmas.