Get Parent navigator

[mkowol-n]

Hi,
Let's say I have MainScreenA divided in half. Top half is some content, and bottom half is NestedNavigation.
NestedNavigation starts with NestedScreenA. Some button navigates from NestedScreenA to NestedScreenB.
Now NestedScreenB wants to get access to the main navigator and navigate from MainScreenA to MainScreenB.

Of course i want to save the state of NestedScreens so when i go back i will see NestedScreenB and after another back - NestedScreenA.
What is the best way to archive that? How can i get parent navigator from nested navigation?