A Russian tale.  When the seventh son of a seventh son is born, it is fortold that he will become king.  The current king discovers this prophecy and proceeds to put an end to it by killing the child.  Years later, the king has a beautiful daughter.  He is out in the kingdom when he sees a young boy that was adopted and finds out that he was found at the place he supposedly killed the young child.  He sends the boy to the castle with a not to kill him immediately.  When he falls into a robbers cave, the man there feeds him a sleeping potion in order to rob him.  When he finds the note from the king, the takes pity and changes the note.  Now, when the boy arrives he weds the king's daughter and the king cannot believe what has happened.  He makes the boy get a golden feather from the griffon's back in order to remain married.  When the boy returns with the feather and more jewels, the king sneaks out to get his fortune also - but never comes back.