Character

I wonder why Trond Sander follows Jon despite his extreme wild side, and what it says about Trond's character.
I just read the passage of the book when Trond and Jon are stealing horses and Trond gets injured, then is bucked off his horse and injured yet again. I think it shows a lot about Trond's character that he would trust Jon like he does in this scene. After falling from his horse over a fence, Trond is laying on the ground, thinking he is paralysed. Jon approaches him on his horse, disagrees and demands that he stand up. Trond obeys. This shows that Trond is trusting; but is he too trusting? Or just trusting enough to live recklessly like this, after running away from home like he has? Will this turn out to be Trond's fatal flaw/hamartia?