Hiccup let go of Toothless.

The moment just like in the movie has passed, when Hiccup let Toothless go so he could start his own family with the Day Fury. Several years have passed. Hiccup is now an adult, and Astrid has long since gotten married and had children. Now he, Astrid, and their two children are sailing alone on a ship, when Hiccup hears the familiar sound of flapping wings—Toothless is flying with him. Toothless, unaccustomed to communication and Hiccup, his pupils narrowed with savagery, lands on the bow of the ship.