What if Hiccup wasn't the only runtlike child of Stoick? What if he had a twin sister? Well, he does. She was carried off by a Monstrous Nightmare, when she was 5 months old, and has this talent with understanding the dragon's feelings. She was brought back to Berk, by accident, when the Nightmare was shot down and killed. She was left in Berk's freezing snow, alone. She never knew about her father or brother, until now. Meet Eira, Hiccup's long lost twin sister.