Books, authors, and reading.

[CLXcool]

Strangely enough, no actual mocking birds were harmed or even mentioned in the book.

Chapter 10. This is where the title comes from.

“Remember it’s a sin to kill a mockingbird.” That was the only time I ever heard Atticus say it was a sin to do something, and I asked Miss Maudie about it.
“Your father’s right,” she said. “Mockingbirds don’t do one thing but make music for us to enjoy . . . but sing their hearts out for us. That’s why it’s a sin to kill a mockingbird.”

Ah. So it was mentioned after all.