How To Update Data In The Database, My Attempt Was Unsuccessful.

I was hoping I could get this to work, so far I can access all the data from the database, but I also want to update it. I placed a button, updateBttn_Click event to update the database.
It's not updating though and I am not gettting any errors. Could you please look at the update query in the update button and see if I have it right. Also, I think it might be because I have the first retrieval of the database tables set to  ExecuteReader(). Do I need to redo this and use ExecuteNonQuery somewhere else?
Thanks in advance. 
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;

public partial class userpage : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
        usrnmeLbl.Text = PreviousPage.CurrentUser;
        hiddenpassLbl.Text = PreviousPage.CurrentPass;
        //Define database connection
        SqlConnection conn = new SqlConnection(
            "Server=localhost\SqlExpress;Database=MyDB;" + "Integrated Security=True");
        //Create command
        //SqlCommand comm = new SqlCommand("SELECT UserName, Password, UserID FROM UsersTable WHERE UserName = '" + usrnmeLbl.Text + "'", conn);
        //SqlCommand comm = new SqlCommand("SELECT Father FROM FamHistTable WHERE UserID IN (SELECT UserID, UserName, Password FROM UsersTable WHERE UserName = '" + usrnmeLbl.Text + "')", conn);
        //SqlCommand comm = new SqlCommand("SELECT FamHistTable.Father FROM FamHistTable INNER JOIN UsersTable ON FamHistTable.UserID = UsersTable.UserID WHERE UsersTable.UserID = '" + usrnmeLbl.Text + "'", conn);
        SqlCommand comm = new SqlCommand("SELECT * FROM FatherHistTable, MotherHistTable, UsersTable WHERE UsersTable.UserName = '" + usrnmeLbl.Text + "'", conn);
        //Open connection
        conn.Open();
        //Execute the command
        SqlDataReader reader = comm.ExecuteReader();
        //Read and display the data

            while (reader.Read())
            {
                string usr = reader["username"].ToString();
                usr = usr.TrimEnd();
                string pss = reader["password"].ToString();
                pss = pss.TrimEnd();
                if (usrnmeLbl.Text == usr)
                {
                    if (hiddenpassLbl.Text == pss)
                    {
                        readDB_Lbl.Text += reader["username"] + "<br />";
                        //readDB_Lbl.Text += "Your User ID is: " + reader["UserID"] + "<br />";
                        readDB_Lbl.Text += "Your Father's name is: " + reader["Father"] + "<br />";
                        readDB_Lbl.Text += "Your Mother's name is: " + reader["Mother"] + "<br />";
                    }
                    else
                    {
                        readDB_Lbl.Text = "User and Password mismatch.";
                    }
                }
            }
                
        reader.Close();
        conn.Close();
    }
  
    }
    protected void updateBttn_Click(object sender, EventArgs e)
    {
        SqlCommand comm = new SqlCommand("UPDATE FatherHistTable SET " + "'famUpdteDDL.SelectedItem.Value'" + "  = " + "'addPrsnTxtBx.Text'" +
 "WHERE UserName = " + "'usrnmeLbl.Text'");
    }

}