This is earned for finding optional collectible #1. If missed on the first run, you can "Play Episodes" and select specific parts of the Episode in order to find the missing optional photos through
collectibles mode. The following collectible is described and can be seen in the video below at 3:00:
After work, walk back to camp, and Finn will sit down by a tree. Speak to them. They will carve a stick and throw it over their shoulder. Pick it up.
Getting all 6 collectibles in this episode will also reward you with the following:
https://www.trueachievements.com/a260746/lost-boys-chronicle...