For the past five years, Scarlet searched far and wide for her precious older twin brother, who had been exiled from Berk because of his friendship with Toothless. She is able to find him, but only to end up getting attacked by him and is forced to fight against him. (If you look closely at Hiccup's eyes, those are tears filling and one of his eyebrows raised with slight remorse)

[There should be a GIF or video here. Update the app now to see it.]

(I don't own the song)