Dim FormIsMinimized As Boolean
 
    Private Sub frmParentChild_Resize(sender As Object, _
        e As System.EventArgs) Handles Me.Resize
 
        If Me.WindowState = FormWindowState.Minimized Then
            'Minimieren notieren 
            FormIsMinimized = True
        ElseIf FormIsMinimized Then            
            FormIsMinimized = False
            MsgBox("Form wird wieder angezeigt")
        End If
    End Sub