go jump off a cliff

One day, at a family reunion I had some fun  watching my little cousin go up to his parents who were both enjoying a nice cool one, if he could have a sip. Quickly his mother responded "no" as did his father, to which he replied, "Why can't I have some? you both are!" to which his mother calmly replied "If your father and I jump off a cliff would you?" This response gave my cousin a smirk, as he replied "No way, if you jumped off a cliff i'd have an effing beer!"