A NodeList that contains all children of this node. If there are no children, this is a NodeList containing no nodes.
The content of the returned NodeList is "live" in the sense that, for instance, changes to the children of the node object that it was created from are immediately
reflected in the nodes returned by the NodeList accessors; it is not a static snapshot of the content of the node. This is true for every NodeList, including the ones returned by the getElementsByTagName() method.