Aube – dawn
I remember being annoyed when I was five or six and some adults had a whole conversation about me while I was sitting there drawing. It was like they believed that so long as they weren’t talking directly at me I wouldn’t understand them. In general, I don’t like it when people treat children like foreign and slightly dim beings. In many ways, the average child is smarter than the average adult. The child just has less knowledge and experience. If an adult were placed in a situation as foreign as a baby is placed in, with absolutely everything being new and unknown, they would end up going crazy.
I think the main difference is just that children can just accept everything as possible, as can be seen in how flexible and responsive a child’s brain is compared to an adult’s (very high neuroplasticity). Their brains literally have more possibilities, with a much greater number of neural connections. As a person ages, decent portion of these connections, the underused ones, are pruned.
This is why a deaf child given a cochlear implant or hearing aids early in life will still be able to learn to talk verbally. The neurons involved haven’t withered off or been reappropriated yet. But after a certain age, this path will be closed off or at least much more overgrown and difficult to enter. You can see this in a child that has been given hearing aids later in life – it’s always going to a little bit more challenging for them to talk verbally then it would normally be (though they might still be loads better than the average person, just not as good as they could potentially be).
Besides openness to possibilities, I don't think children are that different from adults. For me, considering children to be like myself, but more intelligent and ignorant, usually works fairly well with understanding them.