MDI Parent child forms

in visual studio 2010 c#

i need to open a file in the Parent window then show the file contents in the child window.
i have the open file dialog and the display of the child window working.. i just cant get display the file contents into the child window.
I am doing this in the openToolStripMenuItem_Click_1 function.
Any suggestions would greatly appreciated.






 private void openToolStripMenuItem_Click_1(object sender, EventArgs e)
        {
            OpenFileDialog ofdOpenFile = new OpenFileDialog();
            ofdOpenFile.Title = "Select a File To Open";
            ofdOpenFile.FileName = "";
            ofdOpenFile.Filter = "Text Files (*.txt)|*.txt|All Files (*.*)|*.*";
            if (ofdOpenFile.ShowDialog() == DialogResult.OK)
            {
                RichTextBox rtb = GetRichTextBox();

                if (rtb == null)
                {
                  
                    FormChild fc = new FormChild();
                    fc.MdiParent = this;
                    fc.Show();
                  
                    string str = "this is the title bar text";
                    fc.Text = str;

                }

                if (rtb != null)
                {
                    rtb.LoadFile(ofdOpenFile.FileName, RichTextBoxStreamType.RichText);
                }
            }
        }