How to find a missing child tag by comparing 2 xml files?

Tried below code but not working .I just want the node missing on comparing. Value difference is not required.
public void CompareXmlTest1(string RefXml, string InputXml)
{

string childnodeCommon = string.Empty;
string childnode = string.Empty;

FileInfo feedList = new FileInfo(RefXml);
FileInfo feedRequest = new FileInfo(InputXml);

// Load the documents
XmlDocument feedListXmlDoc = new XmlDocument();
feedListXmlDoc.Load(RefXml);

// Load the documents
XmlDocument feedRequestXmlDoc = new XmlDocument();
feedRequestXmlDoc.Load(InputXml);

// Define a single node
XmlNode feedListNode;
XmlNode feedRequestNode;

//Get Child Node Names(New)
string feedListNodeName = string.Empty;
string feedRequestNodeName = string.Empty;
//End

// Get the root Xml element
XmlElement feedListRoot = feedListXmlDoc.DocumentElement;
XmlElement feedRequestRoot = feedRequestXmlDoc.DocumentElement;

// Get a list of feeds for the stored list and the request
XmlNodeList feedListXml = feedListRoot.SelectNodes("/Names");
XmlNodeList feedRequestXml = feedRequestRoot.SelectNodes("/Names");



if (feedListRoot.HasChildNodes && feedRequestRoot.HasChildNodes)
{


try
{
// loop through list of Ref Xml Child Nodes
for (int i = 0; i < feedListRoot.ChildNodes.Count; i++)
{
//Get Ref Xml Node
feedListNode = feedListRoot.ChildNodes.Item(i);

//Get Ref Xml Child Node Name
feedListNodeName = feedListRoot.ChildNodes.Item(i).Name.ToString();

//check Input Xml Child Nodes for any missing with the Ref Xml Child Nodes


//Get Input Xml Child Node Name
if (feedRequestRoot.ChildNodes.Item(i) != null)
{
//Get Input Xml Node
feedRequestNode = feedRequestXml.Item(i);

}
//checks to see if child node names is there or not comparing the Input Xml with Ref Xml
else
{
feedListNodeName = feedListRoot.ChildNodes.Item(i).Name.ToString();

if (string.IsNullOrEmpty(childnode) == true)
{
childnode = "Missing Child Node: " + feedListNodeName;

}
else
{
childnode += "," + feedListNodeName;

}

childnodeCommon = childnode + " for the Parent Node " + feedListRoot.Name;


}


}
}
finally
{
//Console.WriteLine("Result file has been written out at " + _resultPath);
}

}
Response.Write(childnodeCommon);
//feedListXmlDoc.Save(_resultPath);
}