here's a quick example i made...
In Form1 ( the Parent Form )
VB Code:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim frmChild As New Form2()
frmChild.MdiParent = Me '/// tell the child that this is the parent form.
frmChild.Show()
End Sub
Private Sub MenuItem1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MenuItem1.Click
MessageBox.Show("test")
End Sub
then in the child Form ( eg: Form2 )
VB Code:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim frmMain As Form1 = Me.MdiParent '/// tell the parent that this is it's child form.
frmMain.MenuItem1.PerformClick()
End Sub