Sometimes life changes from one moment to the next. It's playground weather outside when Hannah is diagnosed with leukemia. In the fight against the evil cancer cells, Polly, Hannah's favorite cuddle pillow, is always by her side. Polly helps Hannah to get completely healthy again. This book is an illustrated guide through the difficult stages of the illness, from the diagnosis of leukemia to recovery. It clearly explains the disease, the necessary examinations, and treatment steps to young patients, while providing parents with practical medical and psychological support to better cope with the illness together.