|TreeWalker.GetFirstChild (AutomationElement)||Retrieves the first child element of the specified AutomationElement.|
|TreeWalker.GetFirstChild (AutomationElement, CacheRequest)||Retrieves the first child element of the specified AutomationElement and caches properties and patterns.|
An AutomationElement can have additional child elements that do not match the current view condition and thus are not returned when navigating the element tree.
The structure of the AutomationElement tree changes as the visible user interface (UI) elements on the desktop change. It is not guaranteed that an element returned as the first child element will be returned as the first child on subsequent passes.