Problem in MdI form Using c#

Question

Hello every one, I have big Problem in MdI form using C#. well i have one mdi form and have group box of on MDI form. if i open my other form in Mdi from then the group box in over of my other form i dont know how can i hide this control for other forms if u have any idea then let me know its too urgent hope you understand my Problem. thanks in Advance