Lol this would never happen because the patient's age would be right there on their chart. That information would be collected before they even saw a doctor or nurse. Also, a rule like that would never exist in the real world, at least not today, in 2024.
Also, remember that meme that's a screenshot of LA Noire that says "press X to doubt"? Probably no one has any idea what I'm talking about, but basically several years ago there was this detective game set in Los Angeles in the 40s and you get to interview potential suspects and collect information to solve whatever crime, you can either believe them, accuse them of lying, or doubt them and picking the right answers uncovers more info to solve the crime. Anyway, I said all that to say this: this thread would have me button-mashing X. Rectal temps until 18? Lol come on. It's an insult to my intelligence, I don't care about a lie here and there, but hit me with one that isn't so insulting.
And another thing, while I'm at it--I've seen it all on here. I remember someone saying that, as an adult, their nurse friend was aware of their fetish for rectal temps and when she visited the clinic her friend worked at, she got a rectal temp because her friend had noted it in her chart. Cooooome on. No one is going to do that. If someone were stupid enough to put that in a patient's chart, no doctor or nurse either one would abide by that. They'd say, "I don't care what her preference is, I'm not doing that." Doing it would be a huge liability. If one were to do it, it would be the kind of doctor you're eventually gonna end up seeing in the news, because they're probably molesting other patients.