Gelert

Once upon a time a prince and a princess had a baby. When the prince was little, his mother died and the king promised her to always take care of their baby. One day, he went hunting and when he returned home he found a lot of blood in the room and the dog's jaws dripping with blood. The prince thought that Gelert had killed his son and so he killed the dog. Then, he understood that the dog had killed a wolf that wanted to kill the little boy and so he had saved him. The prince was wrong and according to the legend he never smiled again.