C# WinForms minimize frm.Show() when main form is minimized

C# WinForms minimize frm.Show() when main form is minimized

I have a Windows Form that is showing an overlay form:
private void ShowWait()
{
frmOverlay = new Base.frmOverlay("Please Wait...");
frmOverlay.Show(this);
}
This frmOverlay form at the same time is show it shows another form in the
middle (message form):
private void frmOverlay_Load(object sender, EventArgs e)
{
frmPleaseWait = new frmPleaseWait(_text);
frmPleaseWait.Show(this);
}
When I minimize the main form then I can still see the frmPleaseWait form,
is there a way I can minimize all when the main form is minimized?
Thanks a lot.