When I was an intern rotating in the ICU, I happened to be in a room with a third year ICU resident named Jill and her attending. And they were having a conversation like I wasn't in the room.
Jill started complaining to the attending about her resident Max. Max was an intelligent guy, very nice and conscientious, and mature beyond his years. I'd worked with him several times and he was always someone I felt like I could rely on. But I gathered from this conversation that Jill and Max were not getting along.
Max was interested in doing critical care as a career and Jill was complaining about the number of mistakes Max had made that month. Jill was going on and on about how he didn't pay enough attention to details and that he didn't know the patient's meds (so I guess I wasn't the only one). And the attending was agreeing with her. Max apparently also did something bad in terms of having some important code discussion with the family without including the attending.
I felt really bothered by the conversation that Jill was having with this attending (especially the fact that it was right in front of me). I went home feeling conflicted, wondering if I should warn Max that Jill had been dissing him so that he could do damage control.
Ultimately, I ended up not saying anything. Max already knew Jill didn't like him, and I didn't want to be the bearer of bad news. But I always wondered if I did the right thing.