Adds a child window. This is called automatically by window creation
functions so should not be required by the application programmer.
+Notice that this function is mostly internal to wxWindows and shouldn't be
+called by the user code.
+
\wxheading{Parameters}
\docparam{child}{Child window to add.}
Removes a child window. This is called automatically by window deletion
functions so should not be required by the application programmer.
+Notice that this function is mostly internal to wxWindows and shouldn't be
+called by the user code.
+
\wxheading{Parameters}
\docparam{child}{Child window to remove.}