How does one access a super's view controller?

I have a problem and I will try to explain the issue:

1. I have one main UIViewController (Whole screen)
2. I have one secondary UIViewController (setbounds)

3. I added my secondary view to my mainView using this:

   [mainController.view addSubview:secondaryController.view];   
   

4. I created a third controller: modalController, I added it to my secondary controller like this:

   [secondaryController presentModalViewController:modalController animated:YES];
   

5. I make calculus based on some events inside of my modelController.

6. I am able to send messages from my modalController to my secondaryController using:

   [[self parentViewController]  performSelector : @selector(myMethodInSecondaryController:) withObject : myObject afterDelay : .5];
   

   NOTE: "self" corresponds to the modalController

7. I need to pass "myObject" to my mainController, but i cant make reference to my mainController from the secondaryController. I tried this:

   [[self parentViewController] performSelector : @selector(myMethodInMainController:) withObject:myObject afterDelay : .5];
   

   NOTE: "self" corresponds to the secondaryController

   but it doesn't work, i have access to my mainController's view using : self.view.superview

   NOTE: "self" is my secondaryController

but no to its controller.