I was lucky and learned in group therapy, before I was in individual, that any single comment is just part of a whole, much larger relationship and conversation. It was helpful to me in individual therapy when my T let her actual feelings show.

I think asking about another person, usually with T's something "personal," can be triggering no matter how good a therapist you are, especially since they're taught and emphasize that therapy is for the client and it's the client's life that is being discussed. So, suddenly being asked a question about one's own life is going to be a bit jarring and I'd think they might be caught flat-footed and unprepared.

I once mentioned to my T that I thought of her by her first initial (instead of her whole name) and this upset her and she went into a tiny tirade about it being disrespectful, etc. It was horribly embarrassing to me, here I had a little, fond, "nickname" for her but she hadn't understood at that time and I'd caught her unaware and not explained well in my shy disclosure. From then on I was careful to refer to her by her whole name, even in my personal journal! Many many years later (like 15 or so :-) I was brave enough to bring it up again and at that time she too had grown as a therapist and apologized and showed understanding that it had been meant as a loving, "pet" name. But still, now probably 25 years later, I get anxious when I think of her other than by her name.