A man takes his young son to a horse auction. Once there, the man begins examining the stock, running his hands over the horses' necks, along their chests and stomachs, down their legs, over their rumps, etc.
The lad watches with interest, and says: "What are you doing, Daddy?"
"I'm checking these horses to see which one I want to buy," replies the father. At that the young boy bursts into tears.
"What's the matter," asks dad.
"I think," replies the lad between sobs, "the milkman wants to buy mummy!"