Am I the only one that found this creepy, not cute? I mean, trolls in mythology have been known to kidnap children from their parents! Kristoff could be a changeling! He could have a family out there who has no idea what happened to him and thinks he’s dead!

And and and! The trolls in this movie can tamper with memories. Let that sink in.

They may have erased any and all memories Kristoff may have regarding his actual family. Make him believe it was only him and Sven, so he would more readily accept a place in the Troll family group.