Jack, Merida and Rapunzel, the real highnesses of the three main kingdoms, were visiting Berk. Hiccup tried to talk to them several times but he was not allowed to come close (after several attempts, the bodyguards asked Gobber to keep an eye on him, although Gobber didn’t like the situation). BTW, Gobber knew Hiccup didn’t want to get close to them because he “wanted to be their friend”, he knew Hiccup had other interests. In the beginning he thought that Hiccup liked one of the princesses, but then realized his interests were focused on the prince of the Ice Kingdom, Jack (he called him “the ice princess” because one moment ago it was supposed to be a “princess”, and also because in Berk boys are not that pretty :D). Hiccup didn’t want anyone to know but it was too late.