A Glass of Water

A small boy is sent to bed by his father. Five minutes later...
"I'm thirsty. Can you bring me a drink of water?"
"No, You had your chance. Lights out."
Five minutes later: "Da-aaaad..."
"I'm thirsty. Can I have a drink of water?"
"I told you NO! If you ask again, I'll have to spank you!"
Five minutes later...
"When you come in to spank me, can you bring a drink of water?"

credit: PCC