Beezus and Ramona by Beverly Cleary
Nine-year-old Beezus Quimby has her hands full with her little sister, Ramona. Sure, other people have little sisters that bother them sometimes, but is there anyone in the world like Ramona? Whether she's taking one bite out of every apple in a box or secretly inviting 15 other 4-year-olds to the house for a party, Ramona is always making trouble--and getting all the attention. Every big sister can relate to the trials and tribulations Beezus must endure. Old enough to be expected to take responsibility for her little sister, yet young enough to be mortified by every embarrassing plight the precocious preschooler gets them into, Beezus is constantly struggling with her mixed-up feelings about the exasperating Ramona.