Using Tab control how to write text box value carry from one form to another form in windows form c#

Question

Hi

here i am using Tabcontrol in windows forms 

and i am write carry the  textbox value one form to another form 

like this but i am getting error

ss.Controls["textBox1"].Text = textBox2.Text;

            ss.Controls["dateTimePicker1"].Text = Convert.ToString(dateTimePicker1.Value.Date);

           ss.Controls["textBox6"].Text = textBox1.Text;

            ss.Show();

please give me the ans..