Before best-selling author Mel Robbins became one of the world's top podcasters, her life was in crisis as she tried to ignore the $800,000 worth of debt she and her husband owed.br br In a chat with CNN's Sara Sidner, Robbins describes how were life changed after adopting a simple technique. Her latest book, "The Let Them Theory" has found such a dedicated following -- some are tattooing the theory on their bodies.