You downloaded a bootleg of the book a couple months ago.  You pre-ordered seven copies for baby shower gifts, and they arrived today.  Now, you can download the free audio book and listen in hilarious horror as Samuel L. Jackson offers his own dramatic rendition of the soon-to-be-classic [parents of] children's book.

UPDATE:  If you don't feel like creating an audible.com account just so you can download an audiobook you'll listen to once, maybe twice, then check out the youtube version: