Do children and adults understand each other? To some degree, and if many adults have lost touch with childhood, there are some who understand childhood very well. But when I was a child, I wanted to write a book about things adults don't understand about children. (I have since forgotten with what I wanted to write.) There is a gulf. A father can read a Calvin and Hobbes strip, and his little girl can ask what's funny, and the father is in a pickle. It's not that he doesn't want to explain it, and he may be able to explain the humor to another adult, but all of those explanations fail with his daughter. Children often believe that there's a big secret the adult conspiracy is refusing to tell them. And the adult who is trying to get a child to "be serious" by setting aside "make believe" and dealing with what is "real" is like someone who wears a raincoat to the shower. The things that go without saying as part of being serious are in many cases not part of childhood's landscape.
In this sense, children understand each other. This understanding is compatible with friendship, liking, hating, being aloof, and several other things, but there are certain things that go without saying, and the things that go without saying are shared. Two young children will have a world where the difference between "real" and "imaginary" is not very important, where they have no power and adults laugh at things the children don't understand, and where the world is full of wonder. And in that sense two children can understand each other even if they don't know each other's heroes, favorite ways to play, and so on and so forth. And adults likewise understand things that can normally be taken for granted among adults.
Before suggesting that Western Christianity (in other words, Catholic and Protestant Christianity) is best understood in continuity with the