However loving his parents may have seemed, he [Simon] knew that, scratch the surface, and they’d scream and run away. And here he’s confronted with a guy who is just everyting he thinks is wrong about a person, who comes back for him when the chips are down because he’s on his crew. To me, that’s a real parent, and that is an extremely beautiful thing to get to, and I think it’s very real… But the most important thing about ‘Safe’ was that relationship.
—Joss Whedon, Firefly: The Official Companion, Volume One