8) Love thy father and mother. A bro will never ever get with a bro’s biological mother or sister. Step sisters and mothers are fair game.
Rule 8 is almost two rules in one. One being part of the ten commandments, and the other being a known bro code rule. You don't crap where you eat. Therefore a bros biological mother and sister are off limits at all times. Commenting that a mother or sister is hot, is however allowed. A bro should not be offended by any comments like this because why not.
However, step-sisters and step-moms are fair game! If you can bag one then by all means do as you please. A bro will not be offended if you should be successful but you should make him aware of your intentions ahead of time. So that he will have ample time to become very drunk to receive the news of your success.
This rule doesn't require much of an explanation because it is quite obvious to any one with a reasonable intelligence what the rule is all about. What sets bros apart from chicks is the severe lack of drama. Bros don't do drama, we avoid it all costs. The breaking of this rule is bound to cause some measure of drama and therefore should not be done.
Keep the peace my bros, be successful and party hard!