I honestly don't remember ever having an exam at the office with a sibling If I did, it would have been my little sister, because there was a huge age gap between me and my older siblings. (6 years between me and my next oldest brother, where I was only a year older than my little sister.) Perhaps when I was very young. I remember waiting in the waiting room when she was in the office with Mom and vice versa.
Our exams were usually school related, and took place about half passed August. We never discussed anything before or afterwards.. Mom said we were going, reminded us to do exactly as the doctor and/or nurse said, and don't make a fuss.
The only time I can remember being examined with any of the family, other than Mom, may have been around was once when my pediatrician made a house call. (They did that in the '60s still, and he was an old fashioned doc)
I think it was when I had the chicken pox, or maybe the mumps, so we are talking age 6 to 8 or so.
In our kitchen, we had a counter (or bar) that separated the cooking area from the "breakfast nook." (It actually was classified as a half room back then) I remember sitting on the bar in my underwear and him examining me. I know I was feverish, so I don't really know if any of my siblings were there or not. I remember him examining me, and seem to remember getting a shot in the butt. I know I spent the next week or so in bed. I also know I didn't complain. If Mom said "Do this" you just did. There was no discussion, debate, or backtalk.
As I think back on it, it must have been the chicken pox because he also examined my sister, and we both convalesced in Mom's bed. I don't remember watching her exam, or if she watched mine.