Rodentia: Mosela and the Three Kingdoms, by Luke Calder

After Mosela’s village is destroyed by pirate penguins, she embarks on a perilous journey to warn the Mouse King. She must find the Chosen One who is destined to save Rodentia. Khova, the powerful Mage Owl, fits the description perfectly. There is just one problem: Khova is the whiniest, most arrogant creature Mosela has ever met! Will they succeed in saving her family and convince the armies to stand together?