This is the hardest try not to laugh challenge yet! Can you keep a straight face? Chris Hemsworth, Alzheimer's and why ...

The ultimate try not to laugh challenge with Callum. Can you keep a straight face during this funny compilation?

George R.R. Martin is one of the most acclaimed fantasy authors ever, but even he is having trouble with his biggest quest: releasing the next installment in the "Game of Thrones" book series, "The ...