Will and Tux have developed a new game. Tux hides on the trundle beneath Will's bed, and waits, surprisingly patiently, for Will to climb out of bed or reach down and pick up something he's dropped on the floor. Then with a speed and agility seen only from frisky kittens, Tux attacks.
And then they play again, and again, and again, until I finally go in and make those boys Go. To. Sleep.