The child

King Mason of Caldera Cay, the king Defender of the Wing, found a child that appeared on their shores that is born half-dragon named Hiccup. Knowing they couldn't leave the child alone; king Mason raises Hiccup with his daughter Mala. Years later, Hiccup learns he has amazing powers that come with his dragon half. But he has yet to learn that he isn't the only one with powers. And he knew her.

Princess Elsa was born of king and queen of Arendelle, and was gifted with magical abilities of ice. She thought that she was alone and nobody could understand what it was like to live with such a secret. But little did she know that there was another out there. And she knew him.