A very loud, unattractive, hard-faced woman walks into Tesco with her two snotty kids in tow, screaming obscenities at them all the way through the entrance.
The door greeter says, "Good morning and welcome to Tesco, nice children you've got there. Are they twins?"
The ugly woman stops screaming long enough to snarl:
"Of course they bloody aren't! The oldest is nine and the youngest is seven. Why the f*** would you think they're twins?..... Do you really
think they look alike, you dickhead?"
"Absolutely not," replies the greeter, "I just can't believe anyone would shag you twice!"