Porky !
A little girl was leading her dog through the park when an old man stopped her, saying, "That`s sure a pretty dress you`re wearing."
The little girl smiled, "Thank you, Sir. My mama bought it for me. This is my dog Porky."
The old man chuckled, "I`ll bet a nickel I can guess why you called him that."
She shook her head, "I`ll bet you can`t."
He laughed, "You called him Porky because he`s so fat."
She shook her head. "No Sir, we call him that because he fucks pigs."