The difference

Rico says his friend Tex sends along this one:

A young boy went to his father and asked: "Dad, what is the difference between potentially and realistically?"
The father thought for a moment, then answered: "Go ask your mother if she would sleep with Brad Pitt for a million dollars. Then ask your sister if she would sleep with Brad Pitt for a million dollars. Then ask your brother if he'd sleep with Brad Pitt for a million dollars. Come back and tell me what you learn from that."
The boy went to his mother and asked: "Would you sleep with Brad Pitt for a million dollars?"
The mother replied: "Of course I would! We could really use that money to fix up the house and send you kids to a great university!"
The boy then went to his sister and asked: "Would you sleep with Brad Pitt for a million dollars"
The girl replied: "Oh, my gawd! I love Brad Pitt! I would sleep with him in a heartbeat, are you nuts?"
The boy then went to his brother and asked: "Would you sleep with Brad Pitt for a million dollars?"
"Of course," the brother replied. "Do you know what a million bucks would buy?"
The boy pondered the answers for a few days and then went back to his dad. His father asked him: "Did you find out the difference between 'potentially' and 'realistically'?"
The boy replied: "Yes, ‘potentially’, you and I are sitting on three million dollars. But, ‘realistically’, we're just living with two hookers and a queer."