Booth: You know what happened to Cam happened because we had a personal relationship.
Booth: Yeah, people who work in high-risk situations, they can't be involved romantically because it leads to things like what happened.
Brennan: High risk situations?
Booth: Every single day it's with us, there's this line and we can't cross it, you know what I'm saying?
Brennan: Yes, I understand. (She exhales, pondering disappointedly. Parker waves at them.) He seems okay now.
Booth: Yeah, you know, it's important to make things right, we just don't know how. I don't know how.