Oops ! A bit more funny, but not very . Please forget for a while my previous problem, and have a look at this (which is in fact the starting point).

Consider two MDIChild, F1 and F2.
Here is the code :

F1 and F2 are at the beginning unloaded.
MDI form is loaded.

(In F1_Activate, there is F1.Enabled = False)

F1.Show
F2.Show
MsgBox Screen.ActiveForm.Name

We obtain... F1. Interesting not ?