Ada: Inheritance of generics

Hi,

I managed to implement a generic parent class and create a generic unit, 
which is a child of the first one. I wonder, why I have access to 
procedures and functions of the parent class, if I am "within" the child 
unit, but if I am "outside", the compiler complains that no selector for 
a specified function exists.

-- generic parent
generic
   type Modular_Type is mod <>;
package Generic_Parent is
   type Object is abstract tagged limited null record;

   function Example return Integer;
end Generic_Parent;


-- child unit
generic
   -- omitted
package Generic_Child is
   type Object is new Generic_Parent.Object with private;

   function Example return Integer;
end Generic_Child;


-- testsuite
package Parent is new Generic_Parent (2**16);
package Child is new Parent.Object;

-- compiler error, no selector for ...
A : Integer := Child.Example;


My aim is to append some generic childs to a container and iterate
over each item and call a common procedure or function.


Best regards,
   Dennis Hoppe