Little Johnny and his grandfather have gone fishing. After a while grandpa gets thirsty and opens up his cooler for some beer. Little Johnny asks, "Grandpa can I have some beer too?"

"Can you stick your penis in your a**hole?" grandpa asked back.
"No"
"Well, than your not big enough"
Granpa then takes out a cigarette and lights up. Little Johnny sees this and asks for a cigarette.
"Can you stick your penis in your a**hole?" grandpa asked again.
"No"
"Well, than your not big enough"
Little Johnny gets upset and pulls out some cookies. His grandfather says, "Hey, those cookies look good, can I have some?"
Little Johnny asks, "Can you stick your penis in your a**hole?"
Grandpa looks at Johnny and senses his trick so he says, "Well of course I can, I'm big enough."
Little Johnny then says, "Well, then go f**k yourself, these are my cookies"