XML “child” Defined
This post clarifies the meaning of “child”. An XML node may have 0 or more child nodes. A child node is a direct descendent of the parent (i.e. it is one level below the parent node).
Methods such as NumChildrenHavingTag will return the number of direct descendents (i.e. nodes that are exactly one level below the calling node) that match the specified requirements.
For more information, see this XML Child Tutorial