I found a book about the big bad wolf, who is old now and living in a retirement home. A news reporter comes and talks to the Big Bad Wolf and asks him the story of the Three Little Pigs. Every time the BBW told a 'tall tale' they 3LPs would shout "Tell the truth, BBW!" then he would, kinda, tell the truth.
Every time the 3LPs called out the BBW I would place a toy dinosaur in my clients arms, until the end of the book, where he was left struggling to hold onto all the lies.
We then went back through the book and every time the BBW told the truth he was able to take a 'lie' away.
We then talked about how lies build up and up until they are too much for one person to hold onto. We also talked about and practiced how to be honest, even if it means getting in trouble or someone not being happy with us (i.e telling mom when brother is being unsafe, even though brother gets mad, it important not to lie).
*EDIT* So, the book is called "Tell the Truth BB Wolf!" I forgot to include that! Ooopsy! : )