Brandon Sanderson, author of the 'Mistborn' novel series defends 'Game of Thrones' creator George R.R. Martin for sitting on 'The Winds of Winter' for 15 years

Brandon Sanderson, author of the 'Mistborn' novel series defends 'Game of Thrones' creator George R.R. Martin for sitting on 'The Winds of Winter' for 15 years "Some of my writer friends — they've had some mental health challenges... I can't imagine mixing that with the pressure of millions of peop…