Potentially & Realistically

Son: "Dad? What's the difference between potentially, and realistically?

"Its hard to explain, go and ask your mother if she would sleep with Tom Cruise for a million pound,
then ask your sister if she would sleep with Brad Pitt for a million pound,
and finally, ask your brother if he would sleep with David Beckham for a million pound,
and come back to me with the answers." The son says to his mother, "Mum? Would you sleep with Tom Cruise for a million quid?
Mum says "Of course I would!!!"

He says to his sister, "Would you sleep with Brad Pitt for a million quid?"
His sister says, " Yeah! Definitely."

And Finally, the boy asks his brother, "Would you sleep with David Beckham for a million quid?"
His brother says, "A million quid? I suppose so, yeah."

Slightly confused, the boy returns to his Dad

His Dad says, "Well, what did you learn son?"
The son says, "Well...potentially, we are sitting on 3 million quid, but realistically, we are living with 2 sluts and a faggot"