Little Moomin is busy hibernating with his family when he is awakened by a creature warning him that Christmas is coming and that they must get ready. But what is Christmas? And how putting up a tree and decorating it is supposed to help? 
This is a super cute picture book about Christmas that can be read on several levels. The first one is the enchantment of Christmas and its traditions, but the second one comments on how the period creates stress for many people - the Moomin family only encounters anxious neighbours running around trying to get everything ready in time, so that they don't understand if Christmas is a threat or a celebration. I thought that was rather well done, and these characters are adorably cute.