Sqldatareader Within A Loop From Another Reader?

I have an SqlDataReader which loops through records returned from an SP, within that loop I would like to initiate another SP, but for some darn reason the following code won't work:
 // create SqlConnection object
string ConnectionString = ConfigurationManager.ConnectionStrings["aiv3cs"].ConnectionString;
SqlConnection myConnection = new SqlConnection(ConnectionString);

try
{
// Create a new XmlTextWriter instance
XmlTextWriter writer = new
XmlTextWriter(Server.MapPath("products.sitemap"), Encoding.UTF8);

writer.WriteStartDocument();
writer.WriteStartElement("siteMap");
writer.WriteAttributeString("xmlns", "http://schemas.microsoft.com/AspNet/siteMap-File-1.0");

// create the command
SqlCommand myCommand = new SqlCommand();
myCommand.Connection = myConnection;

// set up the command
myCommand.CommandText = "spGetMenuStructure";
myCommand.CommandType = CommandType.StoredProcedure;

// open the connection
myConnection.Open();

// run query
SqlDataReader myReader = myCommand.ExecuteReader();

bool HasSubElements = false;

SqlCommand myCommand2 = new SqlCommand();
SqlParameter myParameter1 = new SqlParameter();
SqlDataReader myReader2 = new SqlDataReader();

// parse the results
while (myReader.Read())
{
// create the command
myCommand2.Connection = myConnection;

// set up the command
myCommand2.CommandText = "spGetMenuSubElements";
myCommand2.CommandType = CommandType.StoredProcedure;

myParameter1.ParameterName = "@ContentID";
myParameter1.SqlDbType = SqlDbType.Int;
myParameter1.Value = Convert.ToString(myReader["ID"]);

myCommand2.Parameters.Add(myParameter1);

// run query
myReader2 = myCommand2.ExecuteReader();

while (myReader2.Read())
{
HasSubElements = true;
}

myReader2.Close();

if (Convert.ToString(myReader["HasPage"]) == "1")
{
writer.WriteStartElement("siteMapNode");
writer.WriteAttributeString("title", Convert.ToString(myReader["PageTitle"]));
writer.WriteAttributeString("description", Convert.ToString(myReader["PageTitle"]));

string PageURL = Convert.ToString(myReader["PageName"]) + "?ContentID=" + Convert.ToString(myReader["ID"]);

writer.WriteAttributeString("url", PageURL);

if (HasSubElements)
{
writer.WriteEndElement();
}
}
else
{
writer.WriteStartElement("siteMapNode");
writer.WriteAttributeString("title", Convert.ToString(myReader["PageTitle"]));
writer.WriteAttributeString("description", Convert.ToString(myReader["PageTitle"]));
}

HasSubElements = false;
}

myReader.Close();

// end the xml document and close
writer.WriteEndElement();
writer.WriteEndDocument();
writer.Close();
}

finally
{
myConnection.Close();
}I've gotten the following two errors:There is already an open DataReader associated with this Command which must be closed first.And a build error:Error29The type 'System.Data.SqlClient.SqlDataReader' has no constructors defined Any suggestions would be most appreciated.