"Mum Knows" joke

Tony man excitedly tells his mother he's fallen in love and is going to get married.

Tony says, "Just for fun, Mum, I'm going to bring over two other female friends in addition to my fianc? e, and you have to try and guess which one I'm going to marry."

The next day, Tony brings 3 beautiful women into the house and sits them down on the couch and they chat for a while.

He then says, "Okay, Mum. Guess which one I'm going to marry."

She immediately replies, "The red-head in the middle."

"That's amazing! You're right, how did you know?"

His mother folds her arms across her chest and says, "I don't like her."