Okay, let's talk about kids and needles.
Because under the post about giving minors the right to medically consent, people are spreading a ton of misinformation on this - largely because they just do not question the stuff they just assume are "normal". Which here is: "kids are all afraid of needles and therefore if we let them consent or not to medical proceedures, they would just not consent and not get vaccinations, because needles hurt".
And, look. Here is the thing: no, needles do not actually hurt a whole lot. And while, yes, certain procedures that involve being stabbed by a needle hurt more if you are younger for a bunch of reasons... that is actually not the main reason children fear needles. Because, again: the pain is not that bad. And most kids, especially young kids, whose motor skills are still developing, usually will have a bunch more hurting scratches, bruises and the like at any given moment than there will be pain from the needle.
No, from what research can tell, the main reason kids are afraid of needles, is more that for many of them needle procedures are very traumatizing. And that is largely because of the consent issue.
Imagine you are a person who is still pretty darn new to that whole human thing. So for one, yes, your brain is actually not that great in understanding what pain is dangerous and what pain is a safe limit of pain. So yes, someone intentionally hurting you (like with a needle) is really kinda scary. But then there is also the thing where this person hurting you is not telling you why they are doing. The people who you normally trust with keeping you safe (your family) is betraying you, by just holding you down and scolding you for crying over it. Or maybe it is not your family, but some strange nurse who is holding you. And while you are scared, because someone is intentionally hurting you, while someone else is restricting you, the adults around you are telling you, that your emotional reaction to this is actually bad and you are wrong for reacting that way. They might in fact lie to you and tell you that something that is insanely scary to you is "not that bad", instead of just understanding that it is super scary to you. And that is then what you start to expect whenever you see a doctor prepare a needle: people holding you down, hurting you without reason, and telling you that you are wrong for being upset, actively gaslighting you.
We have research on this. And this research is pretty clear: most kids are actually somewhat okay with needles, if you inform them why you are doing it, allow for them to have their emotions, talk to them about their emotions, and allow for them to set at least some conditions.
And frankly, I hate how many people just accept the framing of "kids are naturally afraid of this because it hurts". Like, folks, I know y'all are fucking Americans and that in your culture it is kinda normalized to like put kids into like some sort of fortified hamsterball to stop them from like doing typical kids stuff. But... let me tell you: if you do not do that, kids will actually very regularly engage in dangerous play that they know will often end up in injuries that are going to hurt. And, no, they are not to dumb to understand that. The kids know that this is what might happen because of their play. They actually just take the risk. Yes, they will cry if they get hurt, because - again - their nervous system is still calibrating how it relates to pain. But they will likely do that thing again and again. I can tell you: I fell down a tree so often during my childhood, and I still climbed it. Again and again. So did most kids I knew. Like, fuck, we lived next to a forest. We played "Tarzan", and tried to go along paths without touching the ground. And we fell. A lot. And we still did it.
It is not the fear of pain that makes kids afraid of doctors. It is the fear of the associated force, and gaslighting.