using C# VS2003

private void textBox2_KeyUp(object sender,
System.Windows.Forms.KeyEventArgs e)
        {
            if(e.KeyCode== Keys.Enter)
            {
                MessageBox.Show("yay");
            }
        }

This code works fine on my MDI main form, however nothing happens when
I do the same thing in a child form.  Anyone know whats up?