So my main character is a lost princess. She was exiled from the castle when she was a baby (With almost no clues of her lineage) and has been raised by a rural family in the next country. The relations between the two countries are really bad and she lives in the wilderness (Sort of). The villain is a Duke in her original country. Her mother is also missing. What would be a conceivable way for the Duke to find out that she still alive sixteen or so years later?