title: parent dialog state is changed to invisible but child dialog still stays visible
body: <p>In my project code, we are using custom dialogs. I am facing some weird issues with them. 
  I have a child dialogue and a parent dialogue.
  <strong>Ideally a child dialogue goes to invisible state when we invoke</strong> <code>parent.setVisible(false)</code>.</p>
  
  <p>But I am seeing some strange behaviour. 
  When I make <code>parent.setVisible(false)</code> then still my child dialog remains visible but when I try to get <code>child.isVisible()</code> : it gives me false.
  Also when I try to invoke <code>child.setVisible(false)</code>, again it has no effect in visiblity of parent dialog .</p>
  
  <p>NOTE: I cannot show any code sample due to too much complexity, lenght and other external API issues. Also I tried replicating this using external programs but it works as expected and no issues seen.</p>
  
  <p>I just want to know does anybody knows any scenario in which a child dialog control get loosen up when we make <code>parent.setVisible(false)</code>?</p>