Ok going down and kicking his ass if a bad idea. Why? Well easy, he can just retaliate. You could end up getting a bigger beating then you give him. Besides it was your mothers choice to buy the stuff in the first place so get pissed at her, you cousin is only the middle man who sells it. Oh and btw you can get into so much shit for putting your mother in lockdown. Lets see you stold her car her atm her credit cards, yep not looking good. Your better off talking to her about it and if she don't listen...well you have a few choices to make, call the cops on her or learn to live with it. I'd be pissed to, so I see why your mad but think of the outcomes of your own actions, don't fuck your life up because your mother and cousin.