GtkWarning: gtk_button_box_set_child_secondary: assertion `child->parent == GTK_WIDGET (widget)' failed

[Gerald Britton <gerald britton gmail com>]

HI -- I'm getting errors like this from one of my glade files (Gtk.Builder):

GtkWarning: gtk_button_box_set_child_secondary: assertion
`child->parent == GTK_WIDGET (widget)' failed
    self.add_from_file(path)


I'm having trouble finding which widget in the file (there are many)
that is causing this error.  I'm need to know a few  things:

1. when and why is the method gtk_button_box_set_child_secondary
called by the add_from_file method?

2. If this method is called because of something in the glade file,
what is it specifically (so I can find it)?

3. Can the text of the error message be changed to include the name of
the widget that has the problem, if available?


-- 
Gerald Britton