The lin family is in the middle of a fight with the xies and the leis, and the two families are planning to join forces against them. The two families have reached the ninth level of refinement, which means they can no longer compete with each other in the market place. The only way for the lins to fight back is to join with the other families, and that's what they're going to do. They're not going to be able to argue with their father and brother-in-law, so they'll have to resort to violence if they can't talk to each other. The other family is not strong enough to stop them, and they've insulted their father, too. So, the only thing that can stop them is for them to get together and fight.