A man took his Rottweiler to the vet¹ and said to the vet: "My dog's cross-eyed, is there anything you can do for it?"
      
      "Well" said the vet "lets have a look at him"
      
      So he picks the dog up and has a good look at it's eyes.
      
      "Well" says the vet "I'm going to have to put him down"
      
      "Just because he's cross-eyed?" says the man.
      
      "No, because he's heavy" says the vet.