And she's on an important mission. A mission to help Santa! Every Christmas Eve, this tiny mouse brushes away Santa's snowy footprints, nibbles up the mince pie crumbs, and - most importantly - checks on her Santa HQ tablet that all the correct presents are under the tree.

But when Christmas Tree Mouse discovers that baby Ola has received the wrong present, it's a CATASTROPHE! Can she use all her special training and determination to save the day? And might Santa himself make a special appearance?

This charming and heartwarming picture book from Waterstones Children's Laureate Joseph Coelho and debut illustrator Farah Shah offers a brilliantly funny sneak peek behind the scenes on the most magical night of the year. The perfect gift for any child this Christmas!