You should worry about your own life.
Raynor: Sarah is my friend and colleague and she is a wreck. So even though Mackenzie isn't really hers -
Xander: Don't ever say that again!
Raynor: All right, fine. I'm just saying that as a doctor, I took an oath. And when you save a life, you feel responsible for it.
Xander: You should worry about your own life.