Collusion and cheating in my own home... HELP!!!

[cyberer]

I posted this to the other forum too, sorry for the repeat...

As the subject line implies, I have a problem in my home games. We usually get the same crowd of about 14 guys around. Well lately I've been realizing that 3 of the guys playing seem to be colluding. Two of the guys are brothers and the other is a mutual friend of mine and theirs. Here is how it seems to be going when they do it. We usually play with 2 preliminary tables which combine to a big final table. So chances are 2 of the 3 wind up at one table and the other is at another table. So the 2 guys at one table go all in against each other so one gets a mountain of chips. Then the guy at the other table plays really tight and gets to the winner's table. Then the brothers are together at the winner's table. They can often be seen whispering and they both play strong and try to get even more chips. Then when the game becomes 3 handed, the collusion begins in earnest.

When it is 3 handed between the brothers and another guy, whenever the other guy folds one of the brothers also folds so that the brothers dont eliminate each other. Therefore they can wait until the other guy goes all in and both call him to ruin his odds. Then they split the money (I know the brothers split it and i assume that the 3rd guy is in). What can I do?! My home game is going to hell. Please help.