This is what I did. I created a method at the just below the the mdi form constructor like below:
private void SetMaximizedChildFormsToNormal()
foreach (Form form in this.MdiChildren)
form.WindowState = FormWindowState.Normal;
Then where the form form is being called I call the above method before. Like below:
AreaOfLawViews.AreaOfLawMetroForm appForm = new AreaOfLawViews.AreaOfLawMetroForm()
MdiParent = this,
StartPosition = FormStartPosition.CenterScreen,
WindowState = FormWindowState.Maximized
So, the already opened form is set to Normal before the new form is opened and maximized. It is working for me already.
I hope this helps.