Ep 11. Attack the Treehouse

One afternoon, Karl contemplates Peter's treehouse (William has lead him and Theresa there) and he decides to attack it. But it's too dangerous while Peter and Heidi are in the treehouse. So Theresa has an idea; and the next morning, Karl, Theresa and William invade the treehouse before Heidi and Peter arrive. When they realize that, Peter and Heidi are furious, and Peter wants to fight.