Mature Sequels and Series

Books with Sequels

Daddy Long Legs/Dear Enemy
Fiddler’s Gun/Fiddler’s Green
Freckles/Girl of the Limberlost
Eight Cousins/Rose in Bloom
Pat of Silverbush/Mistress Pat

Trilogies

The Lord of the Rings
CS Lewis’s Space Trilogy
Emily of New Moon
Little Women/Little Men/Jo’s Boys

84 Charing Cross Road/Duchess of Bloomsbury Street/Q’s Legacy

Series with 4 or more

All of a Kind Family
Anne of Green Gables series 
Betsy Tacy (High School and beyond books)
Leatherstocking Tales (Last of the Mohicans)
Little Britches series
Scarlet Pimpernel

Series with more than 1 author