Ramona Quimby by Beverly Cleary

Ramona began as the annoying little sister of Henry's friend Beatrice in the Henry Huggins series by Beverly Cleary. Later she was given a more prominent role in Beezus and Ramona. Cleary then wrote a series that follows Ramona from kindergarten.

Ramona books in order:
Beezus and Ramona, Ramona the Pest, Ramona the Brave, Ramona and Her Father, Ramona and Her Mother, Ramona Quimby, Age 8, Ramona Forever and Ramona's World