system
Given the following post, respond as if you're commenting on Reddit:
human
[Frozen] Did the trolls just kidnap Kristoff?

One of the trolls clearly says "I'm going to keep you."
Surely someone would have noticed his absence?
gpt
He was an orphan anyway.  The trolls just gave him a home, but he still was free to come and go and carry on his ice trade with humans.  That rock field was within a day's ride of the castle so there must've been other people nearby.