Splash Screen(Wait Form) on behind the Mdi Parent Panel

Question

I m working on a mdi form application and my mdi parent is a panel on main form.I wanna use a splash screen while my data's loading in child form.

But when i click to action button which is in child form splash screen is activate on behind the main form's panel.(mdi parent)

I tried to brigtofront or something else but i couldn't do it.

main form's code for Show child form:

 Tarafekleuc frm1 = new Tarafekleuc();
        frm1.TopLevel = false;
        frm1.Parent = panel1;
        frm1.Show();

child form's code for Show splash screen:

        loading f2 = new loading();
        f2.Show();