tell me if you hate the idea, but I've found that when troublemakers/rough guys have a younger, innocent (ish) girl looking up at them, they tend to act better.
So, I could offer Sidda. She's feisty, brave and outgoing, and she could handle Dan being rough/troublesome.
He could be not a mentor, but more like a big brother kind of friend. So, she'd like calm him down if he was mad, or he could protect her (ha! like she needs protecting!). So, it'd be a kind of almost brother-sister relationship. What do you think?