In regard to children’s cognitive abilities, it is common knowledge that these do not develop until quite late. In fact, there is a lot of readily available information that says that we do not fully develop those abilities until late in our twenties:
…the cortex, is divided into lobes that mature from back to front. The last section to connect is the frontal lobe, responsible for cognitive processes such as reasoning, planning, and judgment. Normally this mental merger is not completed until somewhere between ages 25 and 30—much later than these two neurologists were taught in medical school.
harvardmagazine.com/2008/09/the-teen-brain.html
If someone would like to dispute this, then please link to anything that would refute it.
There is no doubt that children do accept what you tell them as soon as they are able to understand what you are telling them. Anyone who has had children knows this. And there’s a very good reason for it. They are not capable of working out what is dangerous and what isn’t. You have to tell them, don’t touch that, don’t go there or you will get hurt. Those children that ignore the warnings of those who have the benefit of learned experience will get hurt. It’s evolution 101.
Stories of elves and pixies, Santa Clause, the man in the moon, Jonah being swallowed by a whale, these are all accepted at an early age without question. A five year old will readily accept them. A thirty year old man obviously won’t.
What happens as children grow older is that they understand more of how the world works through practical experience and they correlate this with what they have been told. If there is a disconnect, then they begin to question what they have been told.
Eventually they decide which facts to accept and which to reject. Their decisions aren’t necessarily correct, but whichever ones they do accept will lead to a belief. If they later reject the facts, then they will lose their belief.