Unlike Frank Herbert, he doesn't have kids, AFAIK.
Even so, while his later A Song of Ice and Fire books may not be published in the event of his demise, he has apparently given the makers of Game of Thrones enough info so that they can conclude the TV show appropriately.
Tell like it is, best way Bouncy I should think the the guy was quite young and he thinks it's a doddle just to sit down and write something, he may be a little more appreciable in future about his favorite authors.