Complex sentence: It is not clear whether Laura intended this first draft to be a ninth book in her Little House series, or possibly a standalone novel for adults; much of the material is more for an adult audience than anything in her "Little House" books.
Split into simpler sentences: It is not clear whether Laura intended this first draft to be a ninth book in the Little House series, or possibly a standalone novel for adults. Much of the material is more for an adult audience than anything in her "Little House" books.